So after much time talking about it, and doing research, I’ve finally got around to spending some time on adding Yamaha YM2612 support to the badge computer.
Articles from Techtravels Amiga Blog
Century III Mall is an ailing enclosed shopping mall located in the southern Pittsburgh suburb of West Mifflin, Pennsylvania.
I lived nearby this mall, and this was definitely “our” mall for kids like me growing up in the 1980s and 1990s. I visited the mall in July 2017 because I had heard it wasn’t doing so well, and here are my thoughts and observations.
I’m planning on using the Yamaha YM2612 FM synthesizer chip that has been used in both keyboard synthesizers, but also in the Sega Genesis consoles. The purpose is to add audio capability to my DIY Tablet computer. If you’ve read my other posts, you’ll know that my computer uses the Motorola 68000 processor, so I looked to other 68K machines for inspiration. What did other hardware designers in the 1980s and 1990s choose to use for adding audio to their computers?
I’ve just managed to get some key components working this year, and as a result, the machine is becoming more usable.
I wanted to measure the performance of this Frankenstein machine. Ideally, I’d use standardized benchmarks but I don’t really have a compilation toolchain setup yet. I’m mostly stuck using 68K assembly.
Now that I have the 4MB SRAM board installed, I now have a frame buffer that can keep up with the video bandwidth rate.
The resolution and color depth is currently 800 x 480 x 12-bit. The computing shield I’m using only supports 12-bits, but my LCD can do 24-bit.
Essentially how my frame buffer works is that you write the 12-bit color value into an address in memory that corresponds to a location on the screen.