Jim Rosemary wrote:
This code was taken from a terminal emulator that I wrote a while
back. The entire program was written in machine language and each
revision was burned into an EPROM for the target system. Because of
this, I did not try to make the code too ‘pretty’ – I just wanted to
get it running. Read at your own risk.
Also, be advised that not all keyboards work with my machine. The better
of the two keyboards that I have tried works fine, whereas the cheap one
will not work at all.
It is advisable to obtain the keyboard docs from ftp.ee.ualberta.ca
in the /pub/cookbook directory and read them.
A 6522 is mapped at $fe30
PB0 goes to DATA
PB1 goes to CLOCK
Also, one of the control lines (CB1 or CB2, whichever corresponds
to Interrupt enable $10)
No interrupt code is provided here; only the actual transfer.
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