RANA Systems Elite Controller, User Manual

Page: 186 / 328

ELITE SERIES USER MANUAL THEORY OF OPERATION
Select Bank
TXA Build $Cn00 address
LSR to access controller
LSR slot dependent PROM.
LSR
ORA #$CO
STA ZPAGE+ 1
LDY #$OO
STY ZPAGE
LDA $CFFF Map out other boards
LDA (ZPAGE),Y Map in Elite Controller
LDY #BANK Select Bank 0/1
STA $C800,Y
LDA $CFFF Map out Elite Controller
Read a Byte
READ LDA $CO8C,X
BPL READ
N O T E : $CO8E,X must already have been accessed to
assure Read mode. The loop is necessary to as—
sure that the accumulator will contain valid
data. If the data latch does not yet contain
valid data, the high bit will be zero.
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