Commodore Amiga A500 Technical Reference Manual page 133

RETURN SERIAL PORT STATUS (AH
=
03H)
INPUT: DX
=
Modem Control Register port
OUTPUT: AH
=
Line Status
AL
=
Modem Status
Serial Port Status bits returned in
AX
Register:
AH Reg~ater:
b 1 t l 7 l 6 l 5 l 4 l 3 l 2 l 1 l O l
>
Data Ready
>
Overrun Error
>
Parity Error
>
Framing Error
>
Break Error
>
Transmit hold register empty
>
Transmit shift register empty
>
Timeout Error
AH Register:
b i t l 7 l 6 1 5 1 4 l 3 l 2 l I l O l
>
Delta Clear To Send
>
Delta Data Set Ready
>
Trail~ng edge Ring Detect
>
Delta Receive Line Signal detect
>
Clear To Send
>
Data Set Ready
>
Ring Indicator
I
>
~ e c e i v e Line Signal Detect
KYBDSR ENTRY POINT
READ KEYBOARD INPUT (AH
=
OOH)
VIA S/ W INT 16H
INPUT: DS
=
ROM data segment (0040h)
OUTPUT: AL
=
ASCll CHARACTER
AH
=
SCAN CODE
READ KEYBOARD STATUS (AH
=
0 1 H)
INPUT: DS
=
ROM data segment (0040h)
OUTPUT: AL
=
ASCll CHARACTER
AH
=
SCAN CODE
Z FLAG
=
1 if no character available
Z FLAG
=
0 if character available