PK-88 - Homebrew 8088 SBC powered by Ukrainian i8088 clone (KM1810VM88)

[AndrewDunai]

I've did a lot of 6502 homebrew builds, but this time I decided to do something more complex. Main reasons were:

- Writing a multitasking OS for 6502 is challenging due to RAM banking complexities (though André Fachat nailed it with his GeckOS);

- Writing relocatable 6502 code is hard, and Intel architecture makes it much easier thanks to segment addressing;

- An idea of running DOS on my future homebrew SBC is really exciting.

 

Since Soviet-era chips are still abundant here in Ukraine, I started working on my PK-88 project (PK stands for "Personalnii Komputer").

I've been a regular at 6502.org forums, but since this project isn't 6502-based, I decided to start a thread here.

Shout-out to Matt Sarnoff for publishing his 8088 SBC sources - it gave me a good head start for my build.

 

At this time, I've built a very simple prototype board to play around with i8088. Components used:

- KM1810VM88 - new old stock i8088 clone made by "Kvazar" (which still operates in Kyiv, Ukraine)

- KR580VV55 - new old stock i8255 clone (also "Kvazar")

- AS6C4008 - 512KB SRAM

- W27C512 - 64KB ROM

- ATF16V8 - address & I/O decoding

- 4 MHz system clock

- 74HC00, 2x 74HC573, 4LS244, 74LS273 - glue logic (I/O register with DIP switches & LED array, address latching, etc)

- A nice 20x04 character OLED compatible with popular HD44780

 

 

I'm currently working on V0.2 with more stuff added:

- PS/2 port (through i8255)

- i8253 timer (timed interrupts & simple "PC speaker")

- Interrupt controller (74HC148 & 74HC244)

 

My goal is to make a board similar to TRS-80 Model 100 - a SBC with a display and a mechanical keyboard in a single case. I've did a similar thing with 6502 for my Deck65 project (still haven't assembled it, so here's a render):

 

EDIT: Here's a link to all the schematics & code: https://github.com/and3rson/pk88

Edited October 1, 2023 by AndrewDunai
Added Github link

[Sinyavin]

Nice.

 

 

Offtop: Are you from Lviv, Ukraine, and are you interested in Soviet microelectronics? There was a topic here somewhere about Soviet computers. Perhaps you have something to tell about your local computer PK-01 Lvov / PK-01 Lviv?

 

 

 

 

Check it out.