Commodore Amiga A500 Technical Reference Manual page 131

KYBDSR ENTRY POINT
VIAS/WINT16H
PRINTER ENTRY POINT
VIAS/WINT17H
READ SHIFT STATUS (AH – 02H)
INPUT: DS = ROM data segment (0040h)
OUTPUT: AL = SHIFT STATUS BYTE
CASSETTE INT 15H DSR
OUTPUT: AH - 86h, Error code. Carry set
Interrupts off
READ KEYBOARD INPUT (AH = 00H)
INPUT: DS = ROM data segment (0040h)
OUTPUT: AL = ASCII CHARACTER
AH = SCAN CODE
READ KEYBOARD STATUS (AH = 01H)
INPUT: DS = ROM data segment (0040h)
OUTPUT: AL = ASCII CHARACTER
AH = SCAN CODE
Z FLAG - 1 if no character available
Z FLAG = 0 if character available
READ SHIFT STATUS (AH = 02H)
INPUT: DS = ROM data segment (0040h)
OUTPUT: AL - SHIFT STATUS BYTE
PRINT CHARACTER (AH = 00H)
INPUT: AL - Character to output
DX = Index to Printer table port + 1
(the Status port)
CX = Timeout value
OUTPUT: AH = Printer Status
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