• Please review our updated Terms and Rules here

Search results

  1. gertk

    Stopgap replacing Video ULA in BBC Micro

    Hi, My video ULA recently died in the BBC B here, no clock signals whatsoever, tried it in another BBC and no startup either. I tried replacing it for testing with a GAL 16V8 generating the 4 clock signals(8/4/2/1 MHz), the CRT clock and the throughput/blanking of the SAA5050 RGB signals. So...
  2. gertk

    Flexcable for Tandy 200 LCD

    Hi, Does anybody have a source for the flexcable/flexpcb between LCD and mainboard for the Tandy 200 computer ? Mine has several cracks in the cable and it seems somebody has already tried to repair it with silverglue. For now I attached some standard flatcable to the ends of the original cable...
  3. gertk

    Use Sparc 5 Ultra memory in Sparc Station 5

    Having acquired two 32 MByte Ultra 5 memory modules only to find out that the center notch in the memory module is 1 mm shifted compared to the Sparc Station 5 memory modules. Would it be possible to modify these and use them ? I also noticed that there are two smd resistors (0 ohm) placed at...
  4. gertk

    Amstrad PCW 8256 focus adjustment

    Just acquired two Schneider Joyce aka Amstrad PCW 8256 fixed the floppy drives with new belts and they seem to work fine except one of the screens is a bit out of focus. Alas there seems to be no focus adjustment potmeter. I did find a service manual PDF but is quite unreadable. Any ideas on how...
  5. gertk

    Data General D200 circuit or service manual

    Looking for a circuit diagram of the terminal and keyboard, maybe it is in the service manual ? Could not find a circuit diagram online.
  6. gertk

    Kaypro 4-83 graphic overlay

    Hello, Since the Kaypro 4-83 does not have any graphic capabilities I decided to develop a small simple graphic extension board. The board creates a graphical 560x240 pixel overlay on top of the text display. The board has its own memory. Synchronization with the original video output is done...
  7. gertk

    CPM-ish how to copy to another user area?

    Hello, Fiddling with CPM-ish on the Amstrad NC200 and having massive (32MB!) diskspace in the form of a CF card I would like to tidy up the main user area by copying/moving files over to other user areas. This works: COPY BBCBASIC.COM 1: (enter) If I switch user area with USER 1 the file...
  8. gertk

    Strange disk problem Kaypro selfbuilt bios for harddisk

    Hello, Having added an ISA MFM controller to my Kaypro 4-83 and trying to create a bios for it, I am running into the following problem: Note: Harddrive is C, floppydrives are still A and B (maybe a bit unconventional for CP/M) When the current drive is A: I can succesfully do a dir C: but...
  9. gertk

    Acorn Atom 65C02

    Hello, Trying to get a Rockwell R65C02P3 working in the Atom, the computer starts up normally but then takes no keyboard input. With the NMOS 6502 it runs fine. Anyone else tried this ? The goal is to reduce the power consumption as much as possible. So far I replaced the 6522 with a 65C22...
  10. gertk

    IO address 14H in Kayplus ROM 4-83

    Hi, Just fiddling with a homebrew emulator on the Teensy 4.0 and trying to get a Kayplus ROM (kplus83.rom) working so I can add an emulated harddisk function (the emulator already works with the stock 81-232 ROM and some binary images of the boot floppies on SD card). In the emulator I found...
  11. gertk

    Exidy Diskboot rom analysing

    Hi, In an attempt to create disk support for my ARM based Exidy emulator I tried to understand the Exidy boot rom (the 1979 one from Exidy). This rom is also to be found in the Mess and Java emulators. Disassembling the ROM data was not so easy, the jumps and calls looked like they were...
  12. gertk

    MC14093 with 16 pins ?

    I stumbled upon a 16 pins MC14093BC (ceramic) chip from Motorola Has anyone ever seen these? (in the photo also the normal 14 pin version)
  13. gertk

    DIY Kaypro 4 '83 harddisk controller

    Hello, I have been pondering about using a WD1002-27x controller (PC XT) as harddisk controller for a Kaypro computer (the version without the harddisk option). The WD1002-27x came as a 'hardcard' unit for an XT computer complete with a 30 MB Kalok drive. Needless to say the Kalok drive is...
Back
Top