SAP-1 on FPGA - Ep. 1

In an effort to better understand computer fundamentals, I have been studying the binary language of 0’s and 1’s. I’m trying to connect the dots between my knowledge of programming languages like C#, C, and the acutal code as it’s executed on the computer hardware. This led me to the discovery of a great series of videos on making an 8-bit computer on a breadboard by Ben Eater. If you haven’t seen this series of videos and you have an interest in computer hardware, you should definitely check them out.

December 3, 2023

Custom ROM WBW

I am a big fan of retro homebrew computers. I have a few kits that I ordered from Tindie.com based on the RC2014 model (SC126). To keep it completely retro, I bought a classic amber terminal so I could have that classic user experience. After a few hours of troubleshooting, I determined that the default baud rate on the computer (115,200) was too fast for the terminal. I had to find a way to slow it down.

December 2, 2023

Vga on an Fpga

I spent the evening fiddling with my Mercury 2 FPGA. I also have the Mercury Baseboard that has a VGA port (among other ports) broken out. I connected it to my monitor and started to figure out how to make it draw something. Anything would do, so I went searching for a VGA on an FPGA project that I could follow. I found one here. I had to make slight modifications to it to make it work with the Mercury 2.

November 24, 2023

Speech in C

Writing C programs for speech on the SC126 (RC2014 Compatible) with a SPO256-AL2 Speech Synthesis Chip I spent some time yesterday working with ChatGPT to assist me in writing a moderately complex (based on my personal experience) C program. The program needed to be a port of the following BASIC program: 10 DATA 27,7,45,15,53,3,46,51,45,1,21,3 20 LET LE=12 30 DIM XX(LE) 40 FOR Y = 1 TO LE 50 READ XX (Y) 60 NEXT Y 70 FOR Z=1 TO LE 80 IF (INP(31) AND 2) = 2 THEN GOTO 100 90 GOTO 80 100 OUT 31,XX(Z) 110 NEXT Z This program sends the correct allophones to the speech synthesizer to make it say “Hello, World”.