This is a little description of the repair of a Radio Shack TRS-80 Model 1 for a Friend.
The computer comes with several problems.
- Some IC are dead or in shorted state.
- Keyboard flat cable.
- One key “L” is dead.
Finding the cause of the fault has not been easy, i had to ask for a help to Ian, this dude is an expert of TRS-80 repairs.
How you can see from the photos, i had to replace a number of IC.
- 4 x Video RAM 2102 (Z62 / Z63 / Z46 / Z48)
- 1 x Z80 (Z40)
- 1 X 74LS157 (Z31)
- 1 X 74LS93 (Z32)
Stage of the defect (before and after):
Keyboard repair (replacement of internal contacts):
Micro Computer Technical Reference Handbook:
Download: TRS-80 Micro Computer Technical Reference Handbook (2514)
Turbo Chameleon 64 is an extremely user-friendly cartridge that can be used without opening the computer. It is just plugged to the expansion port of the C64.
The Turbo Chameleon 64 cartridge can also be operated as a stand-alone unit (since it’s basically an FPGA computer like the C-One or the Minimig in a C64 cartridge case), replacing the computer, the floppy drive and the heavy power supply.
When used as a stand-alone unit, a USB power adapter or active USB hub can be used as a power source.
Changelog:
- New VGA controller with new modes and VIC-II sync.
- Tripple buffering mode added for properly displaying IFLI pictures.
- Scale-2x video scaling algorithm added.
- Scanline emulation added.
- In cartridge mode real CIAs registers and interrupts are used (allows use of a modem).
- In cartridge mode real VIC-II registers and interrupts are used (allows use of a lightpen).
- Fixed I/O assignments for FPGA (lower power use).
- Lowlevel SD-card functions now use multiple block reads if possible, which increases linear reading speed by about 40 to 50% (most noticeable on large files, such as REU images)
- BUGFIX: fixed error handling and timeouts of the IEC routines, which makes all related operations more robust.
- BUGFIX: added missing timeouts to SD-card functions.
- Joystick port 1 now also works for navigating the menus.
- BUGFIX: on some C64s pressing shift would result in phantom keypresses (F1/F2) under some conditions.
- NEW: various new VGA modes and other options for the new VGA controller (see manual)
- Improved loading speed of file inside T64 images.
- Improved keyboard handling to make the browser a bit snappier.
- BUGFIX: the size of the character ROM saved by the ROM saver was incorrect.
- BUGFIX: .wav player stops at the end of the file and does not continue playing garbage.
- BUGFIX: files bigger than 2k are displayed correctly by the .txt viewer.
- BUGFIX: when copying files out of a t64 image the resulting file was missing the last two bytes and/or the last block was missing completely.
- BUGFIX: filecopy from/to a IEC device did incorrectly abort after 1 block.
- BUGFIX: filecopy filename character set conversion was broken.
- BUGFIX: AR/RR ROM was not correctly disabled when autostarting programs from the filebrowser with AR/RR enabled as default cartridge.
- NEW: added DOS wedge command (see manual)
- NEW: added load and save commands (see manual)
Download: Chameleon 64 beta firmware 8b (1678)
source: beta.icomp.de
Some new games (Cracked / Trained or Unrealeased) for Commodore 64 have been released from your favorites groups: Genesis Project and Laxity.
Download:
source: csdb.dk
SNDH archive v3.4 released. 73 SNDH-files added or updated!
Ever since the birth of the Atari ST, different chip music formats have had different ways to use them. If you are coding a chip music player for the Atari ST you would have to use dozens and dozens of special ways to replay music.
But in the mid 90′s, BDC of Aura crew became tired of this inelegant system and decided to fix the issue once and for all. He then created the ‘SNDH’ file format. SNDH is actually the original songfile and replaycode with a header bolted on top of the music and replayer. The header has a unified calling interface no matter what type of chip music is hidden beneath it, and it has extended datas about the music.
download: SNDH Atari ST YM2149 Archive v3.4 (1684)
source: sndh.atari.org
Some new games (Cracked / Trained or Unrealeased) for Commodore 64 have been released from your favorites groups: Mayday!, Antarctica and Laxity.
Download:
source: csdb.dk
I have customized the keyboard of my C64 with my alias. I have used some keys of a broken C16.
Autopsy:
The CMOS battery is exhausted, the Hard Disk is deceased.
Thanks to Damiano (Manosoft) for his donation.
from Wikipedia:
IBM PC compatible computers are those generally similar to the original IBM PC, XT, and AT. Such computers used to be referred to as PC clones, or IBM clones. They duplicated almost exactly all the significant features of the PC architecture, facilitated by various manufacturers’ ability to reverse engineer the BIOS using a “clean room design” technique. Columbia Data Products built the first clone of the IBM personal computer by a clean room implementation of its BUTTOX.
Many early IBM PC compatibles used the same computer bus as the original PC and AT models. The IBM AT compatible bus was later named the Industry Standard Architecture bus by manufacturers of compatible computers. The term “IBM PC compatible” is now a historical description only, since IBM has ended its personal computer sales.
Descendants of the IBM PC compatibles comprise the majority of personal computers on the market presently, although interoperability with the bus structure and peripherals of the original PC architecture may be limited or non-existent.
source: wikipedia
Some new games (Cracked / Trained or Unrealeased) for Commodore 64 have been released from your favorites groups: S.E.U.C.K. Trainers United, Really Proud Lamers and Laxity.
Download:
source: csdb.dk
Gallery:
The PETdisk is a new storage device, made by bitfixer, for the Commodore CBM / PET with an IEEE-488 port.
The system is in two parts. A datassette module that makes it possible to play “data” from a PC soundcard to the CBM / PET and play “data” from the CBM / PET to the PC. The IEEE-488 module has an SD card and a micro processor.
You can use the commands LOAD, SAVE and LOAD “$” to load or store data on the SD card. The device number can be changed with a help of a jumper. The USB cable is used to provide 5VDC from the datassette module to the IEEE-488 module.
For more informations,schematics,documentations and price of the kit please visit the site of the author.
Video demostration:
source: bitfixer.com
Micro SwinSID (SwinSID88) is a hardware replacement for legendary SID sound chip which was placed in every Commodore C64 computer and other devices.
Firmware update (20120524):
- This version has only one improvement: fixed audio muting emulation.
Download: Nano/Micro SwinSID - Firmware update (20120524) (2150)
source: forum64.de
The HxC Floppy Drive Emulator is a software and hardware system created by jfdn aka Jeff.
The aim of this project is to replace the floppy disk drive by an electronic device emulating the floppy disk drive (list of supported Computer/Hardware).
There are two differents emulators:
- A USB version which allows to connect the floppy disk drive interface of the computer to a PC via a USB cable.
- A SDCARD version which allows to emulate floppy disks which images are stored in a SDCARD.
Release notes for the HxCFloppyEmulator software v2.0.3.0:
- PRE-RELEASE – IN DEVELOPMENT: HxCFloppyEmulator software v2.0.3.0 (Windows & Mac OS X support !)
Download: HxCFloppyEmulator v2.0.3.0 *BETA* (1164)
source: hxc2001.free.fr
ST-Paint is a Drawing program that lets you make Atari St picture on Windows based PC.
ST-Paint is still in a beta phase and it’s made by Peter Jørgensen same author of the program: Ym2149 Tracker.
Download:
source: fedepede04.dk
Some new games (Cracked / Trained or Unrealeased) for Commodore 64 have been released from your favorites groups: Wrampi, Nostalgia, The Hidden Farts and Laxity.
Download:
source: csdb.dk
Sorry, this entry is only available in Italian.
Some new games (Cracked / Trained or Unrealeased) for Commodore 64 have been released from your favorites groups: Laxity, Mayday!, The Hidden Farts and Nostalgia.
Download:
source: csdb.dk
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