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This thread evolved into something less useful than intended (IMHO). What would be useful is a set of meta-data to be added to files or whole directories which can help finding stuff. A small set of data like brand, model name, year, type or record (photo, disk image documentation, ...) in a...

It seems that a data separator (like the Percom) combined with a clock switch is what you need/want? This Percom Separator could look a lot like the Mapper (). Greetings, Fred Jan Edit: another example of a single density only FDC with data separator...

Hi Eudimorphodon, The LNDoubler is very well documented here: /home/fjkraan/kryten/site/comp/lnw/doc/LNW80_Technical_Reference_Manual_(1982)(LNW_Research_Corp)(pdf).pdf page 198. For the Aerocomp doubler there are KiCAD files, but I still have build and test the board (it has low priority)...

About ten years ago I tried helping Pascal Holdry with reverse engineering of the Mapper I, that was the CP/M modification. According to the attached review, the Mapper II allowed 8" disk to be attached to the E.I. If it is anything like the LNDoubler, it is basically switching the FDC clock...

Isn't the 6303 just a clone of the 6803, which is a subset of the 6801 configurations? Ghidra, or any 6801 disassembler should make something reasonable from the code. The attached file is created with f6dasm (https://github.com/Arakula/f9dasm). Apart from the first part, at first glance, it...

In the end I needed both a new boot disk and a better power supply for the floppy drive. Conclusion: if it doesn't work, never assume you have just one problem :-). Greetings, Fred Jan

Here a write up of my recent attempt to boot a Model 1. The boot process of the Model 1 isn't that complicated, but there are several stages. Each completed stage tells you something about what is working and what not. With my long unused and only partially tested setup, I managed to get...

Ok, when I have the change the manuals will be scanned. There might be a better forum for topics like this, but I haven't found it yet. Greetings, Fred Jan

Does 'here' include bitsavers.org? Greetings, Fred Jan

Today while searching for other serious computer part documentation, I found at Jaak's computer and other vintage equipment two binders with documentation of a Honeywell tape system. Is it worthwhile to scan this? If so, I will loan them next time we try to locate the other documentation...

@brijohn: That is one cool project! I expected it was doable, but didn't want to try it myself. And the box really makes it complete! Congratulations! Fred Jan

The project is now in an almost presentable form with a hackaday page: https://hackaday.io/project/197083-tms70c02-single-board-computer-in-two-parts and a minimal serial monitor at https://github.com/electrickery/TMS70C02-Monitor/tree/main. The development-cycle is quite fast with the...

Up until four years ago I had contact with Emmanuel Roche, not about QX-10's, but early french computer systems, like the Alcyane (https://electrickery.nl/comp/alcyane/). Sorry to hear about his demise, but good to hear some of his QX/10 work will be preserved. Greetings, Fred Jan

The https://electrickery.nl/comp/tms7k/ page now has some more meaningful contents, and an image of the TMS70C02 CPU board. The board currently runs a demo, blinkings some LEDs and sends and receives characters over the serial port. A proper serial monitor is planned, but not yet written. It...

The manuals are: P800InstructionSet.pdf Philips P800 (P852/56/57 ..) Instruction Set (Extended Specification). P800AsmLangSpec.pdf Philips P800 Assembly Language Specification. P800_SystemHandbook.pdf Philips P856M/P857M System Handbook 5122 991...

The QX-10 keyboard interface is well described in the Technical Manual, chapter 7. It is possible to interface a PS/2-keyboard via an Arduino to the QX-10 keyboard scan codes. It wouldn't be perfect, but usable. It uses 1200 Baud, but the clock is provided by the QX-10 main board. I don't expect...

Any progress here? The https://forum.vcfed.org/index.php?threads/epson-px-8-repair.1247444/#post-1384012 RAMTEST might be an option to try here too. Indeed the tape drive is not needed to start up the PX-8. Greetings & succes, Fred Jan

The RAM test ROM tries to identify faulty dynamic RAM chips: https://electrickery.nl/comp/px8/roms/RAMTEST.zip and https://electrickery.nl/comp/px8/roms/dRAMtestManual.txt. But you need a cable from the RS-232C port to a terminal/PC. The code does not use the co-processor, just the Z80, i/o...

Hi Crashedfiesta, 0.8 is indeed not a standard E-series value. If capacitors are a guide, these come in +/- 20% precision. So 1 mH might work too. It is usally only critically for oscillators. If you order a pack of ten and you have a LC-meter, you might select the one with the least induction...

For me it did work, but charging the pack with a reasonable current (10% of capacity, 14 hours) before putting them in the PX-8 might have helped. Usually I keep the charger connected during prolonged usage. Occasionally I try to develop code for the PX-4/PX8. Greetings, Fred Jan