This is a very cool series, it is very interesting to see what is possible with these MPU's. I like your videos and how you do it step for step not just giving a fully featured and working example.
Hi doc! Thanks for your project. I decided to replicate it and... IT WORKS! except the serial disk that won't load... I click "Reload" on the loader app but nothing, the z80 continue to spam "connect a serial disk and press reset"... Do you have any idea of what's appending?
I've loved your series and I think all we need now are the instructions on how to build CP/m, plus maybe the Gerber's so we can all have a play. Hope you bring out more videos like this and the one you did on unijunction transistors which was just brilliant!!! Thank you
Just to add that if you're building CP/m on Windows that you'll want to open the .asm files in Notepad++ and look at the end of each file for extraneous characters that shouldn't be there and also make sure you change the line ending encoding to Windows. The line ending encoding being Unix already will prevent the build from getting anywhere on Windows and once changed to Windows line endings it built in seconds without any issue at all.
@@DoctorVolt I shall try that, thanks for the suggestion. I only went through it all to correct the line endings as the GitHub repo wouldn't build for me from a clean download so maybe I have something else setup wrongly too. Oh well, I managed to get it to compile in the end!
Hi Doctor Volt, I've now built my flash programmer and have the TMS9918A chips, just need the correct crystal now. When do you think you'll get the time to update the github repo with the schematics? I'm really itching to get the PCB's done. I'm certain that we're all intrigued to see what your next video has in store for us and I have to say your channel is one of my favourites by a long way. Keep up the fantastic work and I wish you the very best in the months running up to Christmas 2022!!
Aw, you abandoned the battery backed SRAM sans EPROM idea! That was my favourite part! Is it possible to stabilize the voltage during the power on with judicious use of capacitors? Maybe you tried this and it didn't work? Thanks.
I tried capacitors at almost all places with little success . What helps is a delay circuit that switches the RAM into retention mode before powering down the CPU. However in this case, the user must press a button before he can safely switch off the power supply. And if he forgets to do so, he will need to reload the RAM again. So my conclusion is, that the EEPROM in its compact PLCC32 package is more user frienly and takes less space than the battery and the delay circuit.
This is cool ...but ..can it run doom? I mean the letter versio And what if it can ? And i have another question: what iff you build a old hdd ontroller system for it ??? Its easyer to build (i mean not the ata hdd i mean the veri old versio)
I don´t think so, because I have never seen any port of Doom for any Z80 platform. Yes, it can also drive old (parallel) ata hdd, because CF cards use the same protocol.
There's a demo of "Doom" for ZX Spectrum from the 90's, but it's very low resolution. It's not a port, but it's own thing. The core gameplay is not bad though.
