Newsgroups: comp.sys.cbm,comp.answers,news.answers
Subject: COMP.SYS.CBM: General FAQ, v3.0 Part 3/4
Summary: This posting contains answers to questions that commonly surface in
         comp.sys.cbm.  This posting will tell you enough to get your
         computer connected to a network, fixed, and/or enhanced.  This file
         should be read by new users of comp.sys.cbm before posting to the
         group.  It should also be proofread by users who are currently
         active in comp.sys.cbm.
Keywords: CBM FAQ Help List C64 C128 VIC Modem
Followup-To: comp.sys.cbm
Organization: Brain Innovations, Inc.
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Message-ID: <cbmmainfaq30895@msen.com>
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Expires: 05 Sep 1995
Approved: news-answers-request@MIT.EDU


Archive-name: cbm-main-faq.3.0.p3
Comp-answers-archive-name: commodore/main-faq/part3
News-answers-archive-name: commodore/main-faq/part3
Comp-sys-cbm-archive-name: main-faq/part3
Version: 3.0
Last-modified: 1995/08/04


  ---------------------------------------------------------------------------

  Table of Contents (for this file)
  ---------------------------------

   8.  Operating Systems
   8.1.  What Operating Systems are available?
   8.2.  What is GEOS?
   8.3.  What is UNIX?
   8.4.  What is CP/M

   9.  Demonstrations
   9.1.  Just what is a demonstration, or demo?
   9.2.  What does NTSC and PAL mean?
   9.3.  Where do I get demos?
   9.4.  What is a demo competition?
   9.5   What does FLI, DYCP, etc. mean?

  10.  Emulators
  10.1.  What is an emulator?
  10.2.  What platforms do 64 emulators exist on?
  10.3.  What platforms do 128 emulators exist on?
  10.4.  Are any other Commodore computers emulated?

  11.  Troubleshooting
  11.1.  What do I do for my ill disk drive?
  11.2.  What do I do for my ill computer?
  11.2.1.  What do I do for my ill Commodore 64?
  11.2.2.  What do I do for my ill Commodore 128?
  11.3.  What do I do for my ill keyboard?

  12.  Modifications and Cabling
  12.1.  How can you alter which side a 1571 reads from?
  12.2.  How do I open a C128 power supply?
  12.3.  How do I make a cable to hook my CBM 1902A to my 64 or 128?
  12.4.  How do I build a simple RS-232 interface cable?
  12.5.  How do I build a 2400/9600 bps RS-232 interface cable?

  13.  Enhancements
  13.1.  How do I increase my disk drive's transfer speed?
  13.1.1.  What is a Fastloader?
  13.1.2.  What is a ROM replacement?
  13.1.3.  What are the disadvantages to using a drive enhancement?
  13.1.4.  What other things can I do to speed up the drive?
  13.2.  How do I expand my disk drive's capacity?
  13.2.1.  What is a Hard Drive?  Who sell them?
  13.2.2.  What is 64NET?
  13.3.  How do I expand my computer's RAM capacity?
  13.3.1.  What is a Ram Expansion Unit?
  13.3.2.  What is a geoRAM Unit?
  13.3.3.  What is battery backed GeoRAM (BBGRam)?
  13.3.4.  What is a RAMLink?
  13.3.5.  What is a RAMDrive?
  13.3.6.  How do I expand my C128 Video RAM?
  13.3.7.  How do I expand my C64 internally?
  13.3.8.  How do I expand my C128 internally?
  13.4.  How do I increase my computer's speed?
  13.4.1.  How do I increase my Commodore 64's speed?
  13.4.2.  How do I increase my Commodore 128's speed?
  13.4.3.  Can I speed up other Commodore computers?
  13.5.  How do I increase my computer screen's resolution?
  13.5.1.  How do I increase my Commodore 64's screen resolution?
  13.5.2.  How do I increase my Commodore 128's screen resolution?
  13.5.3.  How do I increase other CBM computers' resolutions?
  13.6.  How do I increase my computer's serial transfer speed?
  13.7.  How do I increase my computer's sound quality?
  13.8.  What other ways can I expand my Commodore computer?

  ---------------------------------------------------------------------------


   8.  Operating Systems

  Most Commodore users aren't aware that each machine has an operating
  system.  Since all Commodore systems come complete with a built in
  operating system and BASIC programming language, the need for an
  operating system is minimized.  However, Commodore's internal OS is
  not always the right tool for the job, so alternate OS systems are
  available for the CBM.


   8.1.  What Operating Systems are available?

  Well, Commodore computers come with a standard operating system
  built in ROM. They also contain a built in BASIC interpreter which is
  normally activated after switching on or resetting the computer.
  If you want alternative options to replace the existing OS, there are a few
  that may suit your needs.  GEOS is the best known, but a number of people
  have made UNIX-like operating system replacements for the Commodore 64 and
  128.  Also, on the 128, CP/M is available out-of-the-box. (see below for
  details on different OS types.)


   8.2.  What is GEOS?

  GEOS stands for Graphical Environment Operating System.  It is a Graphical
  User Interface (GUI) style of OS, and it brings to the Commodore 64 and 128
  integrated applications.  The graphical nature of GEOS allows applications
  to use fonts of any size, bitmaps, and menus and mice.  The system was
  Designed by Berkeley Softworks, now GEOWorks, and is supported now by CMD.
  There are a number of graphical style GEOS applications, like GEOWrite,
  GEOPaint, GEOPublish, GEOTerm, etc.  The system is very easy to use, and
  is very fast, even when compared to other GUIs like Windows and OS/2.

  GEOS can make very effective use of a Ram Expansion Unit, a RAMDrive or
  RAMLink, or GEORam.  GEOS allows you to configure your REU to appear just
  like another (very fast) disk drive, although it does not keep its contents
  when you turn your computer off.  So, any GEOS software that works off of
  a disk will work out of your REU.  Since GEOS is very disk-intensive, this
  greatly improves the performance of your system.  Indeed, some firm GEOS
  adherents have said that they would not use GEOS without a RAM device of
  some sort.

  GEOS will not work with a stock 1700.  To have a RAM drive, in GEOS, you
  must have at least 256K of expansion.  Thanks to patches developed by Jim
  Collette(configure2.1), GEOS also supports 1 Meg, 1.5 Meg, and 2 Meg REUs.

  GEOS files are structured differently from standard Commodore files.  They
  cannot be uploaded or downloaded directly.  Before you upload a GEOS file,
  use the freeware GEOS application convert2.5 by W.C. Coleman to convert it
  to Commodore format.  When you download a GEOS file, you must use the same
  program to convert it to GEOS format.  By convention, GEOS format files
  converted to standard Commodore format have a .cvt on the end; however,
  many converted GEOS files just have the same name as the original GEOS file.
  As a rule of thumb, any GEOS file you download, regardless of the extension,
  must be converted to GEOS format with convert2.5.

  If you download an archive of GEOS files (e.g. a .arc or .sda file
  containing GEOS files), you must first dissolve the archive using your C64
  or C128 in native mode.  The constituents of the archive will be converted
  GEOS files, whether or not they have the .cvt extension.  Each of these
  constituents (which are GEOS files) must be individually converted to GEOS
  format with convert2.5.

  If you need some help with GEOS or any aspect of it, I refer you to Myles
  Skinner at mskinner@julian.uwo.ca.  He is one of many people who use GEOS
  every day and can be of help.


   8.3.  What is UNIX?

  UNIX is an OS that was developed by Bell Laboratories in the 1960's and
  is now used on many workstations.  It is a multi-user, multi-process
  OS that has extensive support from the educational and commercial
  communities.  Internet and Usenet are primarily a collection of UNIX
  workstations networked together.  The UNIX-like OS replacements for
  Commodore computers mainly emulate the shell of UNIX, where programs are
  run by merely typing in their name.  Other aspects of UNIX, such as
  multiple processes are supported by some of the offering, which are:

       Asterix. -   A UNIX-Look-and-feel Shell replacement for 64

       UNIX128. -   A small implementation of UNIX for the 128.

       ACE 128/64.- A new offering which borrows the UNIX shell look for 64
                    and 128.  It is available at ftp.funet.fi in
                    /pub/cbm/csbruce.


   8.4.  What is CP/M

  CP/M stands for Control Program for Microcomputers and is available on
  every Commodore 128.  There is also a CP/M cartridge available for the
  Commodore 64, but it cannot read CP/M disks, just 1541 formatted disks, and
  there are questions concerning its ability to work with all revisions
  of the Commodore 64.  CP/M was very popular in the early eighties before
  MS-DOS became popular.  It requires a Z-80 microprocessor, which the 128
  has, or an 8080 processor, and a disk drive capable of reading CP/M disks,
  such as the 1571.  If you don't need to read existing CP/M formatted disks,
  then a 1541 could also be used.  This operating system is the one that
  MS-DOS was modeled after, so there are a lot of similarities.  If you are
  interested in using CP/M as your primary OS, then please check out the
  newsgroup comp.os.cpm, as they have more info on the current events
  concerning CP/M.

  The version of CP/M used on the 128 is 3.0, commonly called CP/M Plus.
  It is compatible with earlier versions of CP/M but adds some new features.
  The copy of CP/M 3.0 that ships with the 128 was specially modified to allow
  use of the features of the 128, such as the Ram Expansion Unit as a RAM
  disk, the SID chip, and the extra RAM of the 128.

  In the March 1994 issue of dieHard, Mike Gordillo gave an overview of the
  CP/M operating system.  It is one of many such articles that should be read
  by anyone new to CP/M.


   9.  Demonstrations

  Very few Commodore enthusiasts have never seen a demonstration, yet
  many aren't really sure what one is.  Well, since these programs are still
  alive and strong in the 1990's, we need to answer some of their mysteries
  (but not all of them, as their job is to amaze).


   9.1.  Just what is a demonstration, or demo?

  A demonstration, or "demo" as they are known, is a piece of software that
  is designed to provoke a visually and aurally pleasing effect from the
  computer.  This usually involves large amounts of multi-colored graphics,
  complex synthesized or digitized sounds, and orchestrated movement of
  shapes or color schemes on the screen.  Demos originated as introductions
  to "cracked" games, games in which the copy protection had been rendered
  useless.  As time wore on, the standard abilities of the computer were all
  used in demos, and rival "cracker" teams raced to bring out the best demo.
  In the search for the "best demo", demo authors, or "coders", tried to
  maximize the use of the computer in a demo program.  Also, they exploited
  any undocumanted feature the computer could provide.  Since most of the
  circuits in the Commodore computers were multi-purpose, experienced coders
  could use some of their features in non-standard ways. Some examples:

  Removing the top and bottom border.
  Removing the side borders.
  Placing text (text mapped sprites) in the open borders.
  More than 8 sprites on screen at once.
  pseudo interlacing to create illusion of up to 640*400 resolution.

  Since the commercial game market has shrunk significantly over the past
  few years, and since demos are sometimes too involved to be classified
  as a game into, many demos are packaged so they can "stand-on-their-own".
  Users can download a demo, load it up, and run it like any other program.

  As demos got more involved, some coders produced cutting-edge technology
  demos intended to "one-up" their rival coders, while others made artistic,
  but less technically challenging demos for arts sake.  Either way, it is
  important to note that demos are not usually interactive.  They are meant to
  be viewed and listened to.  Demos are mostly passive entertainment, and
  appreciation for the effects generated in a demo increases as one
  realizes the normal limitations of the Commodore line of computers.
  So, sit back, load up a demo, run it, and enjoy.


   9.2.  What does NTSC and PAL mean?

  These two acronyms refer to the type of TV broadcasting signals used
  to create the video picture on your TV or monitor. American, Japanese, and
  Canadians use NTSC, while a good part of Europe uses PAL.  This usually
  makes no difference to programs, as the C64 and C128 in C64 mode always
  present 200 lines of pixels to the video display.  However, since the PAL
  standard allows more lines to be displayed on the screen and has a slower
  screen refresh time, the PAL computer has more time before screen
  refreshes to perform other operations, and also can put more information
  on the screen in some cases, since there are more lines in a PAL dislpay.
  Since demos use highly optimized timing and complex routines to perform
  the effects, some demos can only be written for PAL machines.  Sometimes,
  a demo is written for a PAL machine, but it can be made to run on an
  NTSC machine.  Demos that can run on both machines without any code
  modification are called regular demos, those that can only run on PAL
  machines are PAL demos, PAL demos that have been modified to run on NTSC
  machines are called NTSC-fixed demos, and NTSC demos that have been
  modified to run on PAL machines (rare) are called PAL-fixed demos.


   9.3.  Where do I get demos?

  There is a whole site full of  demos.  They are located in the
  /pub/cbm/c64/demos directory of nic.funet.fi.  See section 5.4 for
  directions on how to transfer files from this site.


   9.4.  What is a demo competition?

  This is a "convetion" where people from the demo "scene" get together.
  They are usually held in Europe, although other countries do have them.
  Coders get together and exhibit previously unreleased  demos in a competition
  where the best ones are ranked according to a subjective scoring system.
  At the end of the competition, the demos are released to the public.  To
  make things somewhat fair, demos are judged according to computer type, so
  Amiga demos do not get judged alongside 64 demos.  These competitions are
  usually held in conjunction with music or art competitions.

  Most demo competitions are held within Europe due to copyright laws and
  stuff.

  Previous pardies (demos parties, or competitions) held were:-

  Event                     Location        Date
  -----                     --------        ----
  Radwar Pardy              Germany         January 1994
  Pardy III                 Denmark         Decemeber 1993
  Chormance & Faces Pardy   Hungary         December 1993
  Elysium Pardy             Poland          Decemeber 1993
  Entropy Pardy             Holland         June 1993
  Assembley '93 Pardy       Finland         May 1993
  The Computer Crossroads   Sweden          April 1993
  Radwar Pardy              Germany         January 1993

  Duration 1993-1994 (March 1994)

  Most pardies are held when all the schools are on hoildays.

  The point of a copy pardy is to go there with your computer, meet other
  computer friends from other groups and swap different warez, meet other
  members of your group and using the combined skills from the members
  (graphics/coding/musix/spreading), write a demo before the closing time for
  the pardy so it can get voted on. The winner comes away with about 300
  Kronar or similar.


   9.5   What does FLI, DYCP, etc. mean?

  Here is a small incomplete list of acronyms used to describe the different
  effects used in demos:

  Compiled by:
                Chief/Padua
                MAD/Padua
                Virus/The Acient Temple (UK)

  Jargon          Description
  ------          -----------

  Different Y/X Routines:

  DYCP          Different Y Char Position.  Can run 4 sinus tables though
                it. Each letter can have a sperate sinus tables per character.
  DYPP          Different Y Pixel Position.
  DYSP          Different Y Sprite Position.
  DYXCP         Different Y/X Char Position.  Like DYCP with coordinate
                X/Y movement. Works with Bobs. (Well is a bob routine really).
  DYPPTT        Different Y Pixel Position Tech Tech. Same as a DYXPP.
                TT means tech tech.
  FPP/FPD       Flexible Pixel Posistion/Fexible Pixel Distance
  FLD           Flexible Line Distance.
  AFLIFPP       Advanced Flexible Line Interpretation Fexible Pixel Position.

  Graphics:

  Graphics      In the upper/lower border (Bitmap/4 Colour)
  FLI           Fexible Pixel Posistion. Full screen.
  AFLI          Advanced Flexible Line Interpretation. Hi-RES same as amiga
                graphics. Gives all 16 colours in an 4x8 character block unlike
                usual 3 found in bitmap.
  Morphing      Picture Coverting from One image to another.
  Ray Tracing   Maths graphics.

  Scrollers:-

  Bob Scroll    Using character to display a text based scroller with light
                source.

  Sprite:

  Zoomers       Sprite based stretching.

                Serious side border routines.
                Sprite stretching above the standard Double Y expansion
                Sprite Multi-Plexing

  Vector:

  Standard      Lots of vector routines, too many to mention.
  Shade
  TV Box
  Shadow
  Vector
  Under
  Rubber
  Morphing
  Glenz
  Light Source
  Pixelized
  Solid Filled
  Plamsa
  Rubber
  Fractal
  Shade Bobs
  Shade Line

  Plotting:

  Star Balls    3D Star Field.
  Dot Potters   Just dot plotters.
  Plot Scroll   Dot Plot scrollers.

  Maths:
  Plasma        Very hard to explain
  Fractals      You know these.

  D011/D018
  D011 Split    Charset on one side of the screen - Vectical splits in
                which is Vecticaliy impossible - an on the other side of the
                split you get a FLI or Bitmap Image).
  Flexer        Bit like a Sprite stretcher.

                Bitmap Hardware Swing/Scroll Swing.
                Veritcal Rasters


  10.  Emulators

  As time moves on, people move to other computer systems, for business resons
  or otherwise.  However, many still long to play Commodore games, use
  Commodore software, and enjoy Commodore demos.  Thus, emulators were born
  to bring the non-Commodore computer owner the enjoyment of owning a
  Commodore.


  10.1.  What is an emulator?

  An emulator is a piece of software that runs on a given platform and
  emulates, or mimics, the operation of another machine.  When the
  emulator loads up a program, the programs runs as though it were running
  on the emulated platform.

  For more information on emulators and their use, please see the emulator
  faq, located in the same directory as this one, under the name of
  cbm.emulation.faq.  The Commodore emulator FAQ is maintained by Russell J.
| Alphey and can also be obtained from him at
+ Russell_Alphey@muwayf.unimelb.edu.au or R.Alphey@agriculture.unimelb.edu.au.

  For those with WWW browsers, the CBM Emulation FAQ is at:

| http://hangar18.acns.nwu.edu/users/aforte/cbm/cbm.emu.faq.toc.html


  10.2.  What platforms do 64 emulators exist on?

  Well, C64S exists for the IBM, and X64 is available for anyone running
  X over UNIX.  There is also some development on a C64 emulator for the
  Macintosh.  If you own an Amiga, you can purchase A64 to allow the Amiga
  to run C64 applications.


  10.3.  What platforms do 128 emulators exist on?

  There is a very basic Commodore 128 emulator bundled available for the
  UNIX platform under X.  It is bundled with X64.


  10.4.  Are any other Commodore computers emulated?

  There is a commodore product called the PET emulator that remaps a
  Commodore 64 to emulate a PET 40 column unit (i.e. PET 4032).  You can
  run this program on a C64 to emulate a PET, or you can run this program
  on a 64 emulator to emulate a PET on an IBM, for example.  You can also
  emulate a VIC-20 on some machines.


  11.  Troubleshooting


  11.1.  What do I do for my ill disk drive?

  If your drive won't even accept input from the computer, and the drive
  light is making some blinking pattern, then the drive may be telling you
  what is wrong.

  No Blink       Kernal (E000-FFFF) ROM or 6522 VIA Failure
  One Blink      6116 RAM Failure
  Two Blinks     Possible Zero Page RAM Failure
  Three Blinks   DOS (C000-CFFF) ROM Failure
  Four Blinks    DOS (C000-CFFF) ROM Failure
  Five Blinks    6116 RAM Failure
  Six Blinks     6116 RAM Failure
  Seven Blinks   6116 RAM Failure
  Eight Blinks   6116 RAM Failure

  1541

  The most common problem facing the 1541 disk drive is alignment.  If your
  1541 has trouble reading commercial disks, or reading disks written some
  time ago, but has less trouble reading recently written disks, chances are
  that your 1541 is out of alignment.  C= service centers will typically align
  a 1541 for anywhere from $20 to $45.  There are also 1541 alignment
  programs, (e.g. Free Spirit's "1541/71 Alignment System") which allow you
  to align a 1541 yourself.  There are those who claim that this does not
  produce good results, but there are others who claim to have had
  satisfactory results with these programs.  There were a couple of articles
  in COMPUTE Gazette and I think RUN on how to do this.  The real problem is
  mechanical in nature and can be over come.  Other products are PHYSICAL
  EXAM 1541 and 1571 versions.

  1571

  The C=1571 drive is normally a double sided drive.  However, it can also
  emulate a 1541 and read single sided disks.  Some of the earlier 1571's had
  older system chips (ROMs) which caused a couple of problems.  One, these
  older drives were typically very slow when writing to the back side of a
  disk.  Two, it would take these drives ~30 seconds to go into single sided
  mode.  To check your ROM version, read the error channel of the disk drive
  right after startup.  On the 128, just PRINT DS$.  On the 64, use:

  10 open15,8,15:input#15,a,a$,b,c:close15:printa,a$,b,c

  Run the program; if the message says v3.0 or v3.1, you have the newer ROM.
  If it has a version <3.0, you probably have the older ROM.

  One problem that might occur is not having the head close enough to the disk
  as required because of the light tension of the spring that pulls the head
  down.  Somewhere I remember that there was supposed to be a replacement
  part.  However, one of the alignment programs suggesting using pennies to
  weight it down and lo and behold it started working.

  1581

  The C=1581 drive is a 3.5" drive that uses DSDD 800K disks.  It is
  compatible with both the C64 and C128, although some programs will not work
  correctly with the 1581.

  A small number of 1581's were shipped with an early version of a controller
  chip which has problems with some software.


  11.2.  What do I do for my ill computer?

  At times, every computer must be serviced.  As the parts supply of Commodore
  equipment dwindles, servicing becomes harder.  However, there are many
  sources in Section 16.2 that can service your Commodore machine, and here
  are some things you can do to service it yourself.


  11.2.1.  What do I do for my ill Commodore 64?

  A common problem with the C-64 is it's power supply.  The C64 power
  supplies are not especially powerful, and have this disturbing tendency to
  fail.  If your computer stops working, first check the power supply.
  Replacement power supplies can be obtained from a number of mail order
  places (e.g. Tenex, Parsec, Inc.).  Additionally, several places advertise
  "heavy-duty" power supplies that come with warranties, and give the C64
  enough power to run a REU.

  If your power supply goes, it can sometimes take other parts of the
  computer with it.  If your power supply has died, but the C64 continues
  to fail with a known working power supply, it is likely that a few of your
  chips got fried.

  Also, another common problem with the C64 is the fuse inside the computer.
  If the system power on light comes on, but you get a blank screen, suspect
  the fuse.  It is usually blown by misinsertion of devices into the computer.


  11.2.2.  What do I do for my ill Commodore 128?

  Like the 1571, the C-128 has an older ROM and a newer ROM.  The differences
  between the two are less serious than is the case with a 1571.  The easiest
  way to tell the difference is to click down the CAPS LOCK key and hit Q
  while in BASIC direct mode.  If you see a lower case q, then you have an
  older ROM.  If you see an upper case Q, then you have a newer ROM.  New ROMs
  can be ordered from (e.g. the Grapevine Group) for about $25.  The ROM chips
  in the 128 are all socketed, so replacing the chips is relatively easy.


  11.3.  What do I do for my ill keyboard?

    Clean it:

    Materials you will need:

    Denatured (rubbing) alcohol, a clean pencil eraser, cotton swabs, a small
    Phillips head screwdriver, a jewellers size Phillips screwdriver, a
    solder iron of some type, and a Commodore 64 computer keyboard.

    Procedure:

    1. FIRST AND FOREMOST. Make certain that you have discharged any static
       electricity in your body by grounding yourself to something like a cold
       water pipe. Otherwise, you could blow chips in your computer if you
       were to touch the wrong things.

    2. Turn off your computer and unplug any and all cords and connectors,
       fast-loaders, modems, etc. (just have yourself a naked (if you will
       excuse the expression) computer).

    3. Thoroughly clean all external connectors and ports with the swabs and
       alcohol. Also, clean all plugs that go into those ports. If the problem
       you had persists, proceed with the following:

    4. On a clean surface, turn your key-board upside-down. Remove the screws
       in the bottom.

    5. CAREFULLY, separate the two halves about an inch. Unplug the connector
       to the "power" LED on the top of the C-64.

    6. Place the two halves flat so that the keyboard is facing  you. The two
       halves will be connected by a wire harness. This harness may be held
       down by tape that must be removed in order to place the unit flat.

    7. Remove the 15 or so brass screws that hold the  circuit  board  under
       the keyboard.

    7a.Unsolder the wires going to the shift-lock key.

    8. Turn the circuit board over. You will see the bottom of the keyboard
       with a rubber "U" under each key, which makes contact with the board.
       You will also see on the circuit board, a pair of gold contacts for
       each key on the C-64.

    9. CAREFULLY wash ALL the rubber "U"'s and the gold contacts with the
       swabs and rubbing alcohol. Allow the alcohol to DRY.

    10.Gently, clean each gold contact with the eraser. BRUSH AWAY THE ERASER
       CRUMBS (I use  a  small  hand-held, battery-powered vacuum cleaner).

    11.Re-clean the gold contacts with the swabs and alcohol to ensure that
       you have removed ALL traces of the eraser.

    12.Reassemble the C-64 in the reverse order of disassembly.


  12.  Modifications and Cabling

  As time wears on, many Commodore owners are turnign to themselves to
  manufacture small interfaces, modify their systems, and perform other
  enhancements.  Here are some common things the user can construct
  himself or herself.


  12.1.  How can you alter which side a 1571 reads from?

  On a 128, you can force the 1571 to go into single sided mode with the drive
  command "u0>m0".  (Issue such a command with open15,8,15,"u0>m0":close15.)
  On the 64, a 1571 defaults to single sided mode, but you can convert it to
  double sided mode (and read full double sided disk in 64 mode) with the
  drive command "u0>m1".  While in single sided mode, you can actually format
  both sides of the disk as separate file systems.  The command "u0>h0"
  selects the regular side of the disk, and "u0>h1" selects the flip side of
  the disk.  Note that the flip side, when formatted this way, cannot be read
  by a 1541; neither side will be readable by a 1571 when the disk is
  inserted upside-down.


  12.2.  How do I open a C128 power supply?

  First, unplug both leads running from the power supply and turn it upside
  down.  Locate four (4) small circles in the bottom; two are in the corners
  and two in the other end a bit nearer each other.

  Find some sharp tool, e.g. pin or nail.  In turn, poke it inside each of
  the cirles, firmly, and pull the caps off gently. They'll come out easily.
  Breaking the caps should not matter, but there is no need to destroy the
  casing in process.

  Unsrew the 4 Phillips headed srews with an appropriate tool.

  Notes:

  This does not apply to the C64 brick!

  Some 128 power supplies do not have rubber feet; rather, they have "L"-
  shaped extensions on the casing.  The caps on these extensions are not
  made of rubber, but can be removed.


  12.3.  How do I make a cable to hook my CBM 1902A to my 64 or 128?

  Here is the diagram used to make a replacement Chroma / Luminence 40
  column cable, that the 1902A uses, to connect to the 64 or 128.

        _______                             ________
      /    3    \      1.  Not Used        /    2    \    *1. Luminance
     / 2       4 \    *2.  Audio          / 4      5  \   *2. Ground
    !             !   *3.  Ground        !             !  *3. Audio out
    !      6      !   *4.  Chroma        ! 1    6    3 !   4. Video out
    !             !    5.  Not Used      !             !   5. Audio in
     \ 1       5 /    *6.  Luminance      \  7     8  /   *6. Chroma
      \____n____/                          \____n____/     7. Not used
                                                           8. Not used
         1902A                                64/128
                            * Actually used


  12.4.  How do I build a simple RS-232 interface cable?

                          RS-232 interface
|                     <Transistors are 2n2222>
  <24 pin edge connector>
  N <-----------------------+-----------+
                           /            !
          22k         !-!>+             !
  M <----/\/\/--------!                 !
                      !---+             !
          1k               \            !  <male db25 connector>
  2 <----/\/\/--------------+------------>-------------------> 2
                                        !
                      +-----------------+
                       \
                        +<!-!                22k
                            !---------------/\/\/------------> 8
                        +---!
                       /
  H <-----------------+

  E <--------------------------------------------------------> 20

  C <---+
        !
  B <---+-------------+
                       \
                        +---!                22k
                            !---------------/\/\/------------> 3
                        +<!-!
                       /
  A <-----------------+--------------------------------+-----> 7
                                                       !
                                                       +-----> 4
                                                       !
                                                       +-----> 1


  If you are having problems with this circuit as it stands, you may wish
  to modify it in this way to reverse the clock signal:

  Disconnect the emitter and collector on the middle transistor of the
  diagram (the one that goes to the H line on the computer side)
  Connect the collector to pin 2 on the 24 pin edge connector (the 5v Vcc
  line), connect the emitter to pin H on the same connector, then connect a
  1k ohm resistor to the same pin H and the other end of the resistor to pin N
  or A.


  12.5.  How do I build a 2400/9600 bps RS-232 interface cable?

+ A new programming technique makes it possible to acheive 9600 bps on an
+ unexpected Commodore 64 without the use of a Swiftlink cartridge.
+ Daniel Dallmann of Germany is the originator of this technique and is
+ currently writing modem drivers for some of the popular C64 terminal
  emulation programs to take advantage of this new technique.

+ The interface described below is a little more complex than the one
+ in Section 12.4, but has many advantages:

+ * The interface generates proper EIA232 (RS-232) voltage levels.
+   The one in Section 12.4 relies on the ability of most newer RS232
+   equipment to handle lower voltages.

+ * The following interface can be used as a direct replacement for the
+   interface in Section 12.4, and will work will all existing
+   telecommunications programs at up to 2400 bps, while providing the
+   necessary interfacing to allow suitably equipped applications to
+   operate at up to 9600 bps.

+ * if you currently own a normal RS232 interface, that interface can be
+   modified to incorporate the new interfacing for 9600 bps operation.
+   (in some cases one line of the old interface has to be disconnected,
+    see note **1 )

+ 9600 bps is the maximum limit this type of technique due to the timing
+ limitations of the C64.  The delay between the activation of the NMI-handler
+ and the falling edge of rxd is too long.  The handler must be called in
+ less than 100 cycles.  That's no problem at 9600 bps, but for 19200 baud
+ (the next higher baud rate), you have only 50 cycles, and that's impossoble
+ (because of VIC-DMA ).  On a C128 in fast mode 38400 baud may be possible,
+ but I don't have a C128, so someone else has to try it out.


+             Schematic of a very simple RS232-Interface:


+   userport                       MAX232         rs232   9pin  25pin
+                               +----------+
+                               !          !
+ (C)    pb0--+                 !          !
+             !                 !    /!    !
+ (B)  flag2--*--------------------O< !---------  rxd     2      3
+             !                9!    \!    !8
+ *7*    sp2--+                 !          !
+                               !          !
+ *6*   cnt2--+                 !          !
+             !                 !          !
+ *L*    pb7--+ <NOTE **1!>     !          !
+                               !  !\      !
+ (M)    pa2--*--------------------! >O---------  txd     3      2
+             !               11!  !/      !14
+ *5*    sp1--+                 !          !
+                 74ls00        !          !
+                 +-----+       !          !
+                 !     !       !  !\      !
+ (D)    pb1-*------>O-------------! >O---------  rts     7      4
+            !   1!     !3    10!  !/      !7
+            +----!     !       !          !
+                2!     !       !    /!    !
+ (K)    pb6--------O<-----*-------O< !---------  cts     8      5
+                6!     !4 !  11!    \!    !13
+                 !     !--+    !          !
+ (1)    gnd------!     !5      !          !---   gnd     5      7
+                7!     !       !          !15
+ (2)    +5V------!     !       !          !     (dsr     6      6)
+               14+-----+       !          !
+                               !          !     (dcd     1      8)
+                               !          !
+                               !          !     (dtr     4     20)
+                       ! !+    !          !
+ (1)    gnd------------! !-----!          !     (ri      9     22)
+                       ! !    2!          !
+                               !          !
+                      +! !     !          !
+ (1)    gnd------------! !-----!          !
+                       ! !    6!          !
+                               !          !
+                       ! !+    !          !
+                     +-! !-----!          !
+                     ! ! !    1!          !
+                     !         !          !
+                     +---------!          !
+                              3!          !
+                       ! !+    !          !
+                     +-! !-----!          !
+                     ! ! !    4!          !
+                     !         !          !
+                     +---------!          !
+                              5!          !
+                               !          !
+ (1)    gnd--------------------!          !
+                             15!          !
+                               !          !
+ (2)    +5V--------------------!          !
+                             16+----------+

+ (x) - connections required for a normal RS232-Interface.
+ *x* - additional connections to go up to 9600 baud.

+ remark: The MAX232 needs 4 capacitors (22uF each)
+         to generate +/- 10volts signals.

+ notes :

+    **1 Some other interfaces use this pin.  In that case you have to cut
+        the connection and change it to new way.  PB7 is normally used to
+        receive the DSR (Data Set Ready) signal from the modem, but this
+        signal isn't supported by all terminal programs.  Because of the new
+        wiring DSR will seem to be active to all 'old' programs, so that
+        there won't be any troubles.


+    Top view of the used ICs:

+         74 LS 00                    MAX232
+         +------+                   +------+
+    inA -!1 \/14!- vcc       +cap1 -!1 \/16!- Vcc
+    inA -!      !-  inC      +cap2 -!      !- GND
+   outA -!      !-  inC      -cap1 -!      !- RS232/txd
+    inB -!      !- outC      +cap3 -!      !- RS232/cts
+    inB -!      !-  inD      -cap3 -!      !- TTL/^cts
+   outB -!      !-  inD      -cap4 -!      !- TTL/txd
+    gnd -!7    8!- outD  RS232/rts -!      !- TTL/^rts
+         +------+        RS232/rxd -!8    9!- TTL/rxd
+                                    +------+
+         4 X NAND
+                                    2 X RS232 transmitter
+                                    2 X RS232 receiver

+       user port (view on C64s backside)

+      1  2  3  4  5  6  7  8  9 10 11 12   (top)
+     ------------------------------------
+      A  B  C  D  E  F  H  J  K  L  M  N   (bottom)

+         1 - GND       A - GND
+         2 - +5V       B - ^flag2
+         3 - ^reset    C - pb0
+         4 - cnt1      D - pb1
+         5 - sp1       E - pb2
+         6 - cnt2      F - pb3
+         7 - sp2       H - pb4
+         8 - ^pc2      J - pb5
+         9 - atn in    K - pb6
+         10- 9V AC     L - pb7
+         11- 9V AC     M - pa2
+         12- GND       N - GND


  13.  Enhancements

  If you like to tinker with your Commodore to get the best possible
  performance out of it, these suggestions and products may help you
  in your quest.


  13.1.  How do I increase my disk drive's transfer speed?

  Since the introduction of the Commodore VIC-20 and the slow serial bus,
  Commodore owners have been plagued by slow disk access.  There are two
  ways to allevaiet this problem, fastloaders and ROM replacements.


  13.1.1.  What is a Fastloader?

  The Commodore 1541 drive and any drive attached to a VIC-20, C64, Plus 4,
  C116, or C16 suffer from very slow read and write times.  This is caused
  by Commodore's haste in "economizing" the IEEE-488 bus used in the PET
  series of Commodore computers into the serial bus.  The IEEE-488 bus
  transferred 8 bits of data at a time, and performed some synchronization
  steps, or handshaking, between bytes.  Commodore reduced the path to 1 bit
  but kept most of the original handshaking, most of which is redundant when
  transferring 1 bit at a time.  Early on, some developers noted that, since
  the 1541 drive was intelligent enough to execute a program loaded into its
  RAM, and the Commodore operating system calls to do disk I/O could be
  bypassed, they could write software that sped up the loading process by
  modifying or completely changing the protocol used on the serial bus.  This
  is the idea behind fastload cartridges like FastLoad, Mach 5, etc...


  13.1.2.  What is a ROM replacement?

  As programs became more complex, some programs would not operate with
  this approach.  Thus, the developers then rewrote parts of the Commodore
  operating system on both the computer and the disk drive, and replaced the
  parts of them that did disk I/O with new pieces of code.  This is the idea
  behind JiffyDos and others.

  The basic idea in speeding up the disk drive is to use more than 1 line
  to transfer data, effectively doubling the transfer speed.  Then, reduce
  synchronization requirements in the protocol to a bare minimum, as
  synchronizing time is time not being used to do transfers.

  The fastload cartridges are handicapped somewhat by the need to transfer
  the portion of the program that runs in the disk drive to the drive using
  the slow speed evry time the drive is used.  This can be alleviated
  somewhat, but the replacement operating system replacement products like
  JiffyDos win the race since they do not need to load code into the drive,
  as it is already there.


  13.1.3.  What are the disadvantages to using a drive enhancement?

  The products are not 100% compatible, as they sacrifice reliability for
  speed somewhat.  That means that a program that does not load due to an
  error while using a fastload product will probably load without the
  fastloading enabled.  Also, some programs can not handle the change in
  loading or reading speed, so these enhancements yield about 90%
  compatibility.


  13.1.4.  What other things can I do to speed up the drive?

  You can also increase the speed of disk drive operation by organizing
  consecutive parts of a file on disk to fall a certain number of disk
  sectors apart.  This is called the interleave or interleaving factor.
  Normally, a 1541 disk drive space consecutive parts of a file 10 sectors
  apart, but you can change that a little to minimize the time needed to find
  consecutive parts of a file.

  Also, the C128 in 128 mode hooked up to a 1571 or 1581 has a built-in
  fastloading scheme called burst loading.  Therefore, if you are in 128 mode
  and hooked up to a 1581 or a 1571, you already have this feature.  However,
  the 128 in 64 mode reverts back to the old slow serial routines, and the 128
  in any mode using a 1541 cannot use the burst load routines.


  13.2.  How do I expand my disk drive's capacity?

  CMD sells hard drives for the Commodore 64 and 128.  They range in sizes
  from 50 Megabytes to 200 Megabytes.

  You can also expand your disk drives on board RAM capacity, and use that extr
a
  memory for better archiving performance.

  Software Support International sells the 1541 RAMBoard, which will increase
  you 1541's memory.  SSI used to market a similar board for the 1571, but they
  have depleted stock and no longer carry it.

  If you have access to an IBM of some kind (preferrably with a hard drive),
  you can use a product called 64NET to hook the drive up to the Commodore.
  64NET consists of a cable which connects the CBM User Port and the IBM
  Parallel Port together, and a program that runs on both machines.  The
  program on the IBM is a standard application, but the CBM part is a wedge,
  so it should integrate seamlessly with some programs.  There is now just
  one copy of the product.  Registered users simply receive a 64NET.KEY
  file that enables SAVING.  There is a student discount of AUS$40.00.

  The product is at version 1.68.03 BETA and has full OPEN/CLOSE/READ/READST
  support, can support 4 gigabyte IBM partitions, and have a built-in
  off-board monitor which includes some dos wedge functions. The
  IBM programs have link-based helpsystems and will run on any IBM
  machine.  The registered version allows saving of files, wheras the PD
  version does not.

  The registered BETA version is available (with upgrade to final version
  free) for AUS$50.00, while the unregistered version is free.  These
  prices do not include the cable that is required for operation.  The cable,
  program, and more information can be received from Paul Gardner-Stephen at
  gardners@ist.flinders.edu.au.  Also, the system can be ordered from:

  In Europe:

  Performance Peripherals Europe
  Germany
  +49 2227 3221

  Michael Renz
  +49 2227 3221

  And in Australia from:

  Russell Alphey
  +61 3 4278558 (A/H
  r.alphey@dce.vic.gov.au

  Paul Gardner-Stephen
  +61 8 277 7479 (A/H)

  The C128 version is close to completion, as is a version for the C65.


  13.3.  How do I expand my computer's RAM capacity?

  13.3.1.  What is a Ram Expansion Unit?

  The original form of RAM expansion available to the C64 and C128 were the
  Commodore REUs (Ram Expansion Units).  These REUs plug into the cartridge
  port, and provide 128K (the C=1700), 256K (the C=1764), or 512K (the C=1750)
  of additional RAM.

  This RAM is not true system RAM however; simply adding a 512K REU to your
  system does NOT mean that your word processor will suddenly be able to edit
  512K larger documents.  A REU will only be used by a program that was
  written to take advantage of an REU.  As a caveat on this, you can use your
  REU as additional RAM for a RAMLink .

  An REU can be used as a Commodore Disk Drive by running the program
  RAMDOS.  This will allow users to save and load files from the REU.

  If you are using CP/M, the REU can be configured to act like a disk drive
  under CP/M.

  Although the C=1764 was originally advertised for the C64, and the 1700 and
  1750 for the C128, any of the three RAM expanders will work with either the
  C64 or the C128.  Note that if you want to use any of them on the C64, you
  need a heavy duty power supply.  The 1764 comes with such a power supply.

  There are hardware hacks that will expand a 1700 or a 1764 to 512K;
  additionally, a 512K REU can be expanded to 1 Meg or more.  The plans are
  at ftp://ccnga.uwaterloo.ca/pub/cbm/hardware.  While it appears completely
  safe to upgrade your REU to 1 Meg, there have been some reports of problems
  with REU's upgraded to 2 Megs.  Sometimes the REU will work fine for a while,
  then fail.  If you are upgrading your REU, it would probably be wise to stop
  at 1 Meg.  If you are still memory hungry, consider a CMD RAMLink.

  If you don't wish to do it yourself, there are people who will do it for
  you, for a fee.  The following individual will do RAM expansions on the
  17xx series. He Has lots of experience doing these modifications. His
  current quoted price for expanding a 1750 from 512k to 1 meg is $60. Call
  for the latest prices.  In addition he can do repairs on the RAM.

  Raymond Day
  9601 Morton Taylor Road
  Belleville, MI 48111-1328
  r.day@genie.geis.com (Contact)
  (313) 699-6727

  On a similar note, Software Support International sells a device called
  the 1750 clone, which functions just like a 1750.  It is not as expandable
  as the real 1750, but can be used where a 1750 is recommended or required.

  13.3.2.  What is a geoRAM Unit?

  When Commodore REUs became hard to find several years back, Berkeley
  Softworks introduced geoRAM, which is a 512K RAM expander.  This RAM
  expander gives you all of the advantages of a 1750 with GEOS.  However, it is
  not 1750 compatible, so it will not work like a 1750 outside of GEOS; it is
  transparent to other programs.  (As a caveat on this, see the info on
  RAMLink)).  DesTerm128 2.0 will not work with a geoRAM plugged in.  A
  special version of GEOS 2.0 (which is bundled with geoRAM) is necessary to
  use geoRAM.  No additional power supply is necessary to use geoRAM.  The
  geoRAM can be upgraded to 2MB also.  Contact Jens-Michael Gross at
  grossibr@buran.fb10.tu-berlin.de for information on upgrading the geoRAM.

  The geoRAM can be used without GEOS if it is installed in a RAMDrive or
  RAMLink.  See Section 13.3.4 for information.

  13.3.3.  What is battery backed GeoRAM (BBGRam)?

  Battery Backed GeoRam is a products marketed by Performance Peripherals
  International, and distributed by both them and other retailers, like
  LynnCarthy Industries, Incorporated.  The unit is actually a geoRAM
  clone, but has battery backup included within the unit.  The unit can be
  ordered in the following configurations:

  512kBytes     $92.97US
  1MBytes      $123.97US
  2MBytes      $165.97US

  13.3.4.  What is a RAMLink?

  RAMLink (RL) is a RAM expansion devices from CMD.  The RAM in these devices
  can be partitioned into native mode partitions (with dynamically allocated
  subdirectories), or 1541, 1571, or 1581 emulating partitions.  Thanks to the
  15x1 emulating partitions, software does not have to be specifically written
  to run with a RL. The RL devices should appear as a disk drive to most
  programs.  One notable exception is DesTerm v2.00, which does not work
  with the RL.  There are few other exceptions, and no major commercial
  program has a problem running with an RL .  The deciding factor seems to be
  whether or not the program uses a drive's internal ram.  The RL does not
  'mimic' having this type of internal drive ram, and if a program relies
  upon this it will not run.  The heavily copy protected Digital Solutions'
  programs use this drive ram for its burst loading routines.  So, even
  though a Maverick/RamBoard combination will write a copy of it to the RL,
  it will fail to boot.  However, these programs, once booted from a 1571,
  will use and access all of RL's many functions for lightening fast loads
  and saves.

  RL has ts own power sources, separate from the computer.  When you turn
  off the computer, the power to the RL is left on, leaving its contents
  intact.  This power supply always remains on.  (For safety from power
  outages, battery backups are also available.)

  RAMLink is a powerful, large device.  It can be configured from 0 to
  up to 16 Megs of RAM, using industry standard 1x8 (100ns) 1 Meg and 4 Meg
  SIMMs.(1x9, and faster Simms can be used.)  The RL is constructed so that
  the user may easily add additional SIMMs at any time.

  RAMLink has a port into which you can plug a Commodore REU or a geoRAM.
  You can configure RAMLink to either leave this RAM device alone, or to use
  the REU/geoRAM's RAM just as if it were part of the RAMLink's RAM.  A
  RAMLink also has a pass-through port, in which you can plug a normal
  C64/C128 cartridge, and a parallel port for a CMD hard drive.  The latter
  greatly improves the transfer speed of data between your computer and the
  hard drive.

  If you have a geoRAM, the geoRAM can be plugged into the RL .  the
  geoRAM then acts as an extra piece of ram-based disk storage.

  The RL comes with a very well documented, thorough, and easily
  referenced User Manual.  Contact CMD for more details.

  Nhat-Viet Phi is compiling a list of RAMLink and RAMDrive owners around the
  world.  The resulting list comprises the RAMLink User's Group (RUG), and
  those individuals are called "RUG-Bees".  Email nhatviet@nucleus.com for
  more information or inclusion in the group.


  13.3.5.  What is a RAMDrive?

  The RAMDrive is similar in function to the RAMLink sold by CMD (see
  Section 13.3.4).  The main differences are the smaller amount of memory
  (1-4 MB) and the smaller size.

  At one time, the RAMDrive was sold by CMD, but is no longer available
  through them However, Performance Peripherals, Inc. still sell the
  RAMDrive unit.


  13.3.6.  How do I expand my C128 Video RAM?

  The original, "flat" C128's came with an 80 column display that had it's own
  display RAM that was separate from the system memory of the computer.  This
  "VDC RAM" was 16K in size.  After Commodore introduced the C128D, they
  changed the design and marketed some versions of the Commodore 128D with
  64K of VDC RAM.  Since them, some programs (e.g. I-Paint, Dialogue128)
  have come out that either need or support 64K of VDC RAM.  Owners of flat
  128's can upgrade their video RAM to 64K either by ordering an upgrade
  plug-in board(e.g. from Software Support International), or by replacing the
  RAM chips themselves.  All that needs to be done is, the two 4416 RAM chips
  next to the VDC chip need to be replaced with 4464 RAM chips.  Note,
  however, that since this involves soldering in tight quarters on your 128's
  motherboard, it is very easy to damage the motherboard or the nearby VDC
  chip.  Whenever you wish to use the extra RAM, be sure to set bit 4 in the
  VDC register 28 (0 = 16kB, 1 = 64kB).


  13.3.7.  How do I expand my C64 internally?

  THE TRANSACTOR magazine published two articles written by Paul Bosacki on
  expanding the Commodore 64.  The first article (in Transactor 9.2) described
  how to expand the 64 to 256kB by swapping RAM chips and contained switches
  to perform some special options.  The second (in Transactor 9.6) describes
  how to expand the Commodore 64 to 1MB, using a 512kB REU and 512kB on the
  motherboard.  In additiopn, this expansion needs no switches to enable
  options, which is an enhancement to the first article.

  The Nordic/Finnish MicroBITTI magazine published a two part article by Pekka
  Pessi on expanding the Commodore 64.  Pessi's design (in MicroBITTI Issues
  1 and 2 for 1987) split the C64 memory map into 4 16kB pages, which could be
  each mapped to any 16kB page in 256kB of memory.  It uses the same approach
  of swapping the 64kB DRAMs for 256kB ones, but does the addressing somewhat
  differently.

  In 1993, Marko Makela, with help from Pekka Pessi, translated Pessi's
  article into English and made it available via the Internet.  It is now
  available from nic.funet.fi in the directory /pub/cbm/documents/256kB.


  13.3.8.  How do I expand my C128 internally?

  Marko Makela has written an article on how to expand the C128 and C128D's
  memory up to 1024kB.  It is compatible with his earlier article on expanding
  the C64 to 256kB, so programs written for the expanded 64 should run on the
  expanded 128 in 64 mode.  The plan and schematic is available via ftp
  from nic.funet.fi in directory /pub/cbm/documents/1028.

  The C-256 and C-512

  Twin Cities 128  issues #30 and #31 have a hardware scheme for expanding
  your 128 to 256K or 512K.  To people who understand banking on the 128, the
  256K modification adds RAM blocks 2 and 3 to your system.  The 512K
  modification adds four more RAM blocks that can be accessed as alternate RAM
  blocks 2 and 3, or as a completely separate set of RAM blocks 0-3.

  As with Commodore REUs, software must specifically support the expanded RAM.
  Since these modifications are relatively new, there is not much software out
  yet that supports the additional RAM.  However, ACE 128 does support this
  expansion without any special drivers.

  The hardware modification, while simple from software's point of view, is
  rather difficult to perform in hardware.  Richard Curcio, the designer of
  the memory modifications, can modify your 128 for you.  See Twin Cities 128
  issue #31 for more information.


  13.4.  How do I increase my computer's speed?

  There are a number of products that can increase the operating speed of
  the Commodore 64.  These products work by turning off the on-board 6510
  and turning on a compatible microprocessor, usually a 65C02 or a 65C816
  in 6502 emulation mode.  These products will work with any software that
  does not mind running up to 4 times faster and does not use any of the
  undocumented opcodes of the 6502 IC.

  Also, for a quick way to gain a small speed increase, please see Section
  17.2.


  13.4.1.  How do I increase my Commodore 64's speed?

  Please note that some of these products are no longer offered for sale
  by the original companies, but can be purchased from individuals as used
  equipment.

  Turbo Master Accelerator for C64.

  The Turbo Master Accelerator is for a C64 (or C64 mode of C128) only, uses
  a Rockwell R65C02P4 microprocessor clocked at 4.09 MHz, has its own 64K of
  fast static RAM and a 32K EPROM, has hardware/software switchable speed
  between 4.09 and normal, and has an enhanced ROM with faster disk routines
  that can also be disabled.  A JiffyDOS compatibility option was available.

  Turbo Process Accelerator for the C64.

  This accelerator, made by Rossm"oller, uses a 65C816P-4 microprocessor
  to operate the 64 at three speeds: 1MHz, 4 MHz, or anything between 50kHz
  and 4 MHz.  The 65C816 is a 16 bit version of the 6502/6510, so it is
  possible to write software for the new IC that takes advantage of the 16
  bit opcodes.

  Flash 8

  This accelerator, the only one being currently produced, is also the
  fastest such accelerator for the Commodore 64 to date.  The module,
  which plugs into the expansion port of the Commodore 64, increases
  the CPU processing speed from 1MHz to 8MHz.  It uses a 65816 CPU
  (The 65816 is a descendant of the 65XX series) running at 8MHz to enable
  the increased speed.  Also, it can be optional expanded to 4 or 8 MB RAM
  onboad.  This product is the successor to the Rossmoeller TurboAccess 4MHz
  accelerator card.  The unit has the capability to provide 10x speed disk
  access via a parallel cable and has a CP/M option.

  GEOS compatible requires the special patches that are available from the
  manufacturer, and games or demos which do very intensive timing or raster
  effects might not fucntion correctly.  At present, the accelerator only
  works on PAL 64s of certain revisions and will not function on a C128 in
  64 mode.  Currenlty, the REU is not supported.

  From the advertisement:

    "FLASH 8 is a GEOS-compatible module for the expansion port with a 65816
     CPU that speeds the C64 to 8Mhz by highest compatibility with existing
     software.  Additionally to the original Commodore Kernal a JiffyDos
     kernal is available. You can choose between two different kernals via
     DIP-switch.  Flash 8 comes either with 256 Kbyte or 1 Mbyte RAM onboard.

     A CP/M-emulator for running Z80-CP/M-Software, a macro-library and
     assembler for the 65816 in native-mode are included."

  The prices are:

  349 DM (~$245.00 US) for the unit with 256kB RAM.
  449 DM (~$315.00 US) for the unit with 1MB RAM.

  It is being manufactured and sold by Discount 2000 and Performance
  Peripherals, Inc.


  13.4.2.  How do I increase my Commodore 128's speed?

  The ZIP card for your C128.

  This accelerator was not produced.  Its development has been stopped due
  to miscellaneous problems.  There are no accelerators for the 128 or 128D
  at this time.


  13.4.3.  Can I speed up other Commodore computers?

  Although it is possoble to accelerate just about any Commodore machine,
  no commercial products exist to speed up other Commodore computers.


  13.5.  How do I increase my computer screen's resolution?

  Although the Commodore computers once reigned in terms or screen
  rsolution and number of colors available, newer machines have surpassed
  it in both areas.  Depending on whether you want more characters on the
  screen or more colors at one time, these products might help.


  13.5.1.  How do I increase my Commodore 64's screen resolution?

  Since the Commodore 64's VIC-II cannot be expanded, the only way to increase
  the resolution of the Commodore 64 is to turn off the on-board video and
  replace its output with one from another IC.  The simplist approach
  involves attaching an 80 column video chip (6545, 6845, etc.) to the C64
  via the expansion port.  This will provide 80 columns of monochrome text.
  However, this is only useful for text applications, as most of these video
  devices are not capable of doing high resolution graphics.  Also, none of
  the following are currently produced, but many are sold as used equipment
  by users.

  Batteries Included BI-80

  This unit combined an 80 column monochrome text video display (using the
  6545 IC) and BASIC 4.0.  Either options could be turned on or off via
  software control.

  DATA 20 80 column unit

  This unit preceded the BI80 unit, and was produced from 1982-1984.

  Protecto Enterprizes Protecto-80

  This was basically a repackaged DATA-20 unit.  Some circuitry was changed
  to permit price reduction, but the same functionality is there.


  13.5.2.  How do I increase my Commodore 128's screen resolution?

  The Commodore 128 comes equipped with an second video display controller
  in addition to the 40 column VIC chip.  This chip can be used while in
  64 mode through clever programming, and the controller's standard 640*200
  pixel size can be expanded to 640*400.  However, there is no way to
  completely overcome the color limitation of 16 colors


  13.6.  How do I increase my computer's serial transfer speed?

  If you wish to operate serial devices at speeds faster than what the
  internal software emulated UART can handle, you will need to purchase
  a UART interface.  There are a couple of different kinds, and each has
  its advantages.

  To use these hardware UARTs, the appliaction must be written to take
  advantage of the device.

  SwiftLink

  the SwiftLink cartridge is manufactured by CMD and allows speeds up to
  38.4 Kbps.  This device contains a 6551 UART and plugs into your cartridge
  port and supplies you with a standard 9-pin serial port.  You then connect
  the desired modem.  Dialogue128, Novaterm64, and Kermit(v2.2s) support
  the SwiftLink.

  HART Cartridge

  The HART cartridge is a device similar to the Swiftlink in size.  However,
  the HART unit conatins an 8255 UART IC and can handle speeds up to 57.6Kbps.
  The unit is manufactured by Hatronics.

  DataPump

  DataPump is a set of plans used to build a device that functions just like
  a Swiftlink.  The plans are available at many FTP sites.


  13.7.  How do I increase my computer's sound quality?

  SID Symphony

  The C64 and C128 come equipped with 1 Sound Interface Device (SID) IC.
  This provides 3 channels of output.  For more channels, one can purchase the
  SID Symphony cartridge from CMD to provide 3 extra channels.  Most newer
  sound playing and editing software is able to use the extra channels.

  There are also a number of units one can purchase or build that will
  provide MIDI capabilities for Commodore 64 and 128 users.


  13.8.  What other ways can I expand my Commodore computer?

  There are many hardware items that you can use.  Below is a list of a few of
  them.  Note that some of these items may no longer be in production, and
  thus are only available as used equipment.

  80-Line Simplified Digital I/O Board

  This unit has 40 TTL input lines and 40 separate buffered digital output
  lines plus an expansion socket that could support a standard ROM or clock/
  calendar cartridge.  It works on the C64 and all modes of the C128
  (including CP/M mode).  Its model number is the SS100 Plus.

  "Original Ultimate Interface"

  This is a universally applicable dual 6522 Versatile Interface Adapter board
  with four 8-bit fully bidirectional I/O ports, eight handshake lines, and fou
r
  16-bit timer/counters.  It has IRQ interrupt capability and is expandable
  to four boards.  It works on the C64 and all modes of the C128 (including
  CP/M mode).  Its model number is the 641F22.

  A/D Conversion Module

  This unit is 16 channel, 8-bit, 100 microsecond conversion time.
  Piggy-backs on the 641F22 and thus requires it to operate.  Works on the
  C64 and all modes of the C128 (including CP/M mode).  Its model number is
  641F/ADC0816.

  The Spartan Apple ][+ emulator for the C64, by Mimic Systems, Inc.

  In addition to allowing the use of Apple ][+ hardware/software, this
  device boasted four software selectable C64 cartridge slots, a non-
  dedicated 8-bit parallel port, and standard audio cassette deck
  capabilities for the C64.

  ROM upgrades are available for the C-128 and the 1571.

  C64 Games Port Expander  (Model #8401) 40/80 column converter.

  Switchable, it has 4 independent cartridge sockets plus a 5th switch
  position accessing an 80 col. character set ROM - (limited usability
  because it *apparently* accesses a C64 Ram location which interferes
  with a lot of stuff, I forget where or how) - and a 6th switch position
  independent of the cartridge port for general use stuff.

  It was built into a neat steel housing designed to sit flat on the desktop
  and slide into the cartridge port at exactly the right height.



