Commander X16

Wow, what a great way to get people to stop doing all software development for the x16. Don't bother writing 6502 code, because that's going to be obsolete. And don't bother writing code for this new machine either, because you're going to do the same thing you did with the x16: make breaking change...

I'm thinking the maximum frequency for streaming audio from SD is probably 15360 Hz (Vera audio rate of $27 is close, its 15328 Hz). That way when the FIFO only has 1024 bytes remaining you'd load the next 3072 bytes in the buffer, neither overflowing nor underflowing.

(I'm almost making it but don't quite have the proper Audio parameters yet. It works fine on the Emulator in HOSTFS but i get Audio artifacts on hardware because of the FIFO running empty. For audio I've been using 12970 Hz 16 bit mono. That puts 2594 bytes in the FIFO every 1/10 of a second. By th...

I've done a number of these over the years. The main bottleneck is getting data from the SD card to VERA. I've managed 20fps for a distorted image (2.35 to 1 converted to 160x32 pixels, then using VSCALE to stretch the vertical back to proper proportions). I've got some ideas for converting video to...

The cassette tape software, if it's still hiding in the Kernal, uses Golden RAM as a buffer. SD is light-years better.

The only line of BASIC in my programs is:
1 SYS 1024

What!? How can you use 255 opcodes and still be called RISC :P j/k (it's not) It's at least uniform instruction length? Sorting through the dynamic instruction length of the now-ancient System/3 was a pain. Nah. In fact, depending on operating mode, the same command can be two or three bytes, or so...

voidstar wrote: ↑Thu Nov 07, 2024 12:27 am The C is just for CMOS, right? Lower power and such? So subtle electrical differences, and who-knows-what "undocumented opcode" differences.

http://wilsonminesco.com/NMOS-CMOSdif/

I don't think there are any undocumented opcodes on the 816. They used all of them.

TomXP411 wrote: ↑Sat Nov 02, 2024 11:04 pm I would start with the Commodore VIC-20 User's Guide, which does an excellent job teaching BASIC. Then I'd modify the machine-specific instructions to work with the Commander.

I consider that book the gold standard.

Well, since r44 they've announced a second processor as a drop in replacement. So now the book needs to be twice as long.