Unfortunately, I do not have a modern camcorder (I have a Sony digital-8 camcorder, and a Canon mini-DV camcorder), and my cellphone doesn’t seem to be able to focus very well, so I ended up using my Sony camcorder on a tripod to record this latest video, which is supposed to be in 720p, but it looks more like 320.
Anyway, here is the latest update on my 8088 homebrew computer. I have added a VT82C42N PS/2 keyboard/mouse controller. Continue reading →
I finally got around to posting the code for MemDump, a program I wrote for my 8088 computer (back in July, last year *eye roll*) to display the contents of memory. I have used it extensively so far to see if my interrupts and interrupt vector table (IVT) are installed correctly in low memory.
I restarted my homebrew 8088 computer from scratch, and replaced the original 2 KB of SRAM with 384 KB (I left room in the memory map to add 256 more KB for a final total of 640 KB). I also wrote a firmware program to initialize the interrupt vector table, added an interrupt controller, completely redesigned the control signal demultiplexing circuitry (which both improved the efficiency and decreased the complexity), and wrote a simple demo program to display a memory dump in hexadecimal.
Back in 2013 I wanted to learn how to build a homebrew computer, like what hackers and hobbyists did back in the 1970s during the homebrew computer craze. Although I was about 40 years late, I wanted to make a homebrew computer of my own. Sure, there are much better computers nowadays, but unless you can make circuit boards that have REALLY small solder connections, you can’t really make your own from scratch.