Posted By
Litwr
on 2016-12-27
10:30:56
|  Re: PC RS232 Mouse project for Plus/4 User port_a cheap and working one :-)
I've just written some codes to translate ACIA 3 bytes to X and Y current coordinates.
LDA ACIA1
and #$0c
asl
asl
asl
asl
sta label1+1
lda ACIA3
and #$3f
label1
ora #0
adc current_Y ;we may add some checks here to prevent cursor from leaving the screen
sta current_Y
lda ACIA1
and #3
clc
ror
ror
ror
sta label2+1
lda ACIA2
and #$3f
label2
ora #0
adc current_X ;possible checks
sta current_X
It looks easy.  There is also problem how to distinguish TED and ACIA IRQs?
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