Table of Contents
Note: This IBM PC BIOS API call is for DOS/Win16 personality only. Use Family API for portability.
Note: osFree Macro Library provides macros for most of functions
@AuxInit
Brief
Initialize serial port
BIOS Interrupt
Family API
Syntax
@AuxInit port, settings
Parameters
- port (WORD) - port number
- settings (BYTE) - port settings
Baud rates is passed in the high order 3 bits as follows:
| 000 | 110 baud |
| 001 | 150 baud |
| 010 | 300 baud |
| 011 | 600 baud |
| 100 | 1200 baud |
| 101 | 2400 baud |
| 110 | 4800 baud |
| 111 | 9600 baud |
Bits 4-3 define parity:
| 00 | no parity |
| 10 | no parity |
| 01 | odd parity |
| 11 | even parity |
Bit 2 defines stop bits:
| 0 | 1 stop bit |
| 1 | 2 stop bits |
Bits 1-0 character length:
| 10 | 7 bits |
| 11 | 8 bits |
Return
- AX - port status
Bitfields for serial line status (AH):
| Bit(s) | Description |
|---|---|
| 7 | timeout |
| 6 | transmit shift register empty |
| 5 | transmit holding register empty |
| 4 | break detected |
| 3 | framing error |
| 2 | parity error |
| 1 | overrun error |
| 0 | receive data ready |
Bitfields for modem status (AL):
| Bit(s) | Description |
|---|---|
| 7 | carrier detect |
| 6 | ring indicator |
| 5 | data set ready |
| 4 | clear to send |
| 3 | delta carrier detect |
| 2 | trailing edge of ring indicator |
| 1 | delta data set ready |
| 0 | delta clear to send |