*
* DMAF2 REGISTER TESTING PROGRAM 
*
ADDREG EQU $F00D START OF DMAC REGISTERS 
OUTCH  EQU $F80A CHARACTER OUTPUT ROUTINE 
DRVREG EQU $F024 DRIVE SELECT LATCH

 ORG $0100
START LDX #ADDREG LOAD ADDRESS OF REGISTERS 
 LDB BYTE
 STB 0,X STORE IN REGISTERS 
 STB 1,X
 STB 2,X
 STB 3,X
 STB $21,X
 STB $22,X
 STB $23,X
 LDB 0,X START READING DATA 
 BSR TEST
 LDB 1,X
 BSR TEST
 LDB 2,X
 BSR TEST
 LDB 3,X
 BSR TEST
 LDB $21,X
 BSR TEST
 LDB $22,X
 BSR TEST
 LDB $23,X
 BSR TEST
 INC BYTE INCREMENT THE PATTERN
 LDB #$FE SELECT DRIVE 0 
 STB DRVREG
 BSR DELAY WAIT AWHILE
 LDB #$FD SELECT DRIVE 1 
 STB DRVREG
 BSR DELAY
 LDB #$FF
 STB DRVREG DESELECT ALL DRIVES 
 LDA #'+
 JSR [OUTCH] PRINT A +
 BRA START RE-DO THE TEST

TEST CMPB BYTE COMPARE THE DATA 
 BEQ OK
 LDA #'X OUTPUT A X IF ERRORS 
 JSR [OUTCH]
OK RTS

DELAY LDX #$FFFF
DEC LEAX -1,X
 CPX #0
 BNE DEC RTS

BYTE FCB 0 TEMPORARY STORAGE LOCATION 
 END START