Commander X16

I think that everybody agrees upon the need for more and better documentation. Improvements have been made, and some more are being discussed on the Discord channel. The number of persons doing this in their spare time is low. If you want to give something back to the community, taking part in docum...

Understood. Either way, I’m willing to help if you go about recovering the SMC

Sorry to hear that happen. If the SMC is bricked you can recover it yourself. But you need to have some device to program it with, for instance: - an Arduino Uno, https://github.com/X16Community/x16-smc/blob/main/doc/recovery-with-arduino.md or - a TLL866 series programmer If you have any of those, ...

EDIT: also - my IBM Model F (1981-1983) keyboard didn't work with the X16 (it's a very ancient and picky keyboard), but the IBM Model M's did work for me with a DIN to PS/2 adapter. i.e. look for IBM keyboards with the F-keys along the top (avoid the one with the F-keys at the left side). I think t...

As a side note:
is a common pattern in 6502 assembly when you need to disable interrupts but want to preserve the original state of the interrupt flag.

Without digging deeper it's hard to be sure, but I have at least a theory why it first worked, and not in the cartridge ROM. When the boot_cartridge function is called during Kernal init from within the start function in kernal/cbm/init.s, interrupts have been disabled with a SEI instructions. When ...

Looking at this code that you posted earlier, one thing that stands out is the PLP at the end of _setup_irq. This will disable interrupts, if interrupts were disabled at the beginning of the function, effectively overwriting the CLI. _setup_irq: nop php sei stz ClockLo stz ClockHi lda #<loop_irq sta...

I have a minimal example that works in the emulator. File: cart.cfg MEMORY { ZP: file = "", start = $0022, size = $0080 - $0022, define = yes; CARTRAM: start = $1000, size = $8f00, define = yes; CARTROM: start = $c000, size = $3fff, fill = yes, fillval = $aa; } SEGMENTS { SETUP: load = CAR...

I can try to fix if you upload the complete source code file here + the ca65 config file

It's been a while since I implemented an ISR in ROM, and some things have changed. This is what I think you need to look out for: - On IRQ, the ROM bank is set to 0 by hardware - Consequently, the vector at $fffe in ROM bank 0 is always called - That vector points to Kernal RAM code at $038b - The R...