Chapter 8 - Using MS-DOS
8-26
PL-5910 Series User Manual
Function 11h
Forced 1 Byte Data Send
Regardless of the other party's data flow control, a bit of data is sent.
Input:
AH = 11h
AL = Transmission Data
DX = Port Number (0 to 3)
Output:
AH = Line Status
AL = Transmission Data
Function 12h
1 Byte Data Reception (Immediate Reply)
Receives 1 byte data. Responds immediately if no data is present in the reception
buffer.
Input:
AH = 12h
DX = Port Number (0 to 3)
Output:
AH = Line Status (If not data is present, bit 7 changes to "1"(timeout)
AL = Reception Data
Function 13h
Read Expansion Transmission Port Status
When expansion settings are used, reads the condition of the data transmission
port.
Input:
AH = 13h
DX = Port Number (0 to 3)
Output:
AH = Line Status
AL = Modem Status
BX = Current Data Reception Amount
CL = Condition of Flow Control
Bit 0
Sending (Here) Terminal's XON/XOFF
0: OFF, 1: ON
Bit 1
Sending (Here) Terminal's RTS
0: OFF, 1: ON
Bit 2,3
Unused
Bit 4
Receiving (There) Terminal's XON/XOFF
0: OFF, 1: ON
Bit 5
Receiving (There) Terminal's RTS
0: OFF, 1: ON
Bit 6,7
Unused
