Post by mirkosoft on Oct 29, 2019 12:58:11 GMT
Hi!
I'm trying ro make real GO128.
I know - it looks like impossible, but I have few notes from old C128 Alive forum where we discussed it. I found notes after disk recovery. Disk failed longer time ago.
So, the notes:
; program the keyboard read line ($dc01) into a write line. And set bit 4 to output 0 volts, like this
; Then set the normal keyboard write line ($dc00) to ouput 5 volts on bit 7 like this
; Then print a message to press SPACE
; When the user presses SPACE, this should short out the CIA
; If the transistors inside are powerful enough, it will drop the 5V power supply low enough
; to cause the machine to reset
; But it also might burn out the CIA, blow a fuse, or otherwise burnout some component
; This is unlikely, as you can do something similar with an incompatible joystick
*=$1300
lda #$ff
sta $dc03
lda #$ef
sta $dc01; Then set the normal keyboard write line ($dc00) to ouput 5 volts on bit 7 like this
lda #$ff
sta $dc00
rts; Then print a message to press SPACE
; When the user presses SPACE, this should short out the CIA
; If the transistors inside are powerful enough, it will drop the 5V power supply low enough
; to cause the machine to reset
; But it also might burn out the CIA, blow a fuse, or otherwise burnout some component
; This is unlikely, as you can do something similar with an incompatible joystick
Yes, it can damage some components.
The problem is pressing SPACE. There's really better option to simulate the keypress by software similar method - or if you know - by other.
Can anybody help? Or have idea?
Thank you.
Miro
I'd rather press the reset button, I don't think this fits a purpose.
