stoked that I was able to transfer data from apple IIe to modern laptop over serial just now. Turns out that in addition to an *actually* standards-compliant usb-to-RS232 cable, I needed to stty some options (and not just baud rate/stop bits/parity bits!) correctly on /dev/ttyUSB0 on the Linux side of things, and that was holding me back for a long time.
@jcreed They is really cool. I'd bet curious to know what options.
@mtomczak "raw" is a stty convenience abbreviation that encompasses a huge pile of more primitive options if I understand right
@mtomczak istrip strips the 8th bit, which the apple IIe's peculiar variant of ASCII always has high for printable characters, -ctrlecho prevents echoing control-C as the two-character "^C", -echo prevents echoing entirely (which I sometimes leave on for debugging)
@mtomczak the main thing I *don't* know yet is which flag controls whether it buffers input until it sees a newline --- but in any case "raw" disables this buffering and forwards stuff immediately, as I desired
@mtomczak also I'm not even mentioning the extra things I had to do in:
(a) making sure the serial card was not in slot #3, which is magically reserved for the phantom "80-character display card" which in later apple II models was built-in
(b) physically setting dip switches on the serial card correctly
(c) physically removing and rotating a jumper block on the serial card, which in that orientation acts as a null modem
(d) typing some arcane commands into BASIC to set baud rate apple-side
@mtomczak the next step I want to achieve is being able to send and receive bytes from assembly by directly manipulating the control registers in the memory-mapped peripheral I/O ports
Thankfully https://6502disassembly.com/a2-rom/ has the full firmware listing!
@mtomczak I still need to whittle it down to the ones that actually matter, but:
stty -F /dev/ttyUSB0 300 cs8 cstopb -parenb raw Istrio -ctrlecho -echo
is working well for me