Appendix
App-25
PL-5700 Series User’s Manual
INT 15h Other System Services
Operatio n
Input
O
utput
Setting RS-232C
line mode
AH =
AL =
DX =
00h
Line mode/Parameter
B its 7, 6, 5: B aud rate
B its 0, 0, 0: 110 Baud
B its 0, 0, 1: 150 Baud
B its 0, 1, 0: 300 B aud
B its 0, 1, 1: 600 B aud
B its 1, 0, 0: 1200 B aud
B its 1, 0, 1: 2400 B aud
B its 1, 1, 0: 4800 B aud
B its 1, 1, 1: 9600 B aud
B its 4&3: P arity
B its X , 0: No parity
B its 0, 1: Odd parity
B its 1, 2: E ven parity
B it 2: Stop bits
B it 0: 1 bit length
B it 1: 2 bit length
B its 1&0: Word length
B its 1, 0: 7 bits
B its 1, 1: 8 bits
P ort No.
S ending 1-byte
data
AH =
AL =
DX =
01h
Data to s end
P ort No.
AH = Line control s tatus
B it 7: Time over error
B it 6: Transmis s ion s hift register
empty
B it 5: Transmis s ion hold regis ter
empty
B it 4: Break detected
B it 3: Framing error
B it 2: Parity error
B it 1: Overrun
B it 0: Data ready
R eceiving 1-byte
data
AH =
DX =
02h
P ort No.
AL =
AH =
R eceived data
Line control status
R eading
communication port
s tatus
AH =
DX =
03h
P ort No.
AL =
AL =
Line control status
Modem status
B it 7: Carry detected
B it 6: Call signal received
B it 5: Data-s et ready
B it 4: Transmis s ion enabled
(CTS)
B it 3 - 0: Not in use
Operatio n
Input
O
utput
Wait time check
AH =
AL =
E S:BX =
C X:DX =
83h
00h: Interval timer s tart
01h: Interval timer stop
E nd flag address
Wait time in 1 µs ec units
C Y=
=
0: S ucces s fully completed
1: Error
