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====== @AuxInit ======

===== Brief =====

Initialize serial port

===== BIOS Interrupt =====

[[en:docs:bios:api:int|INTH]]: [[en:docs:bios:api::|H]]

===== Family API =====

[[en:docs:fapi:]]

===== Syntax =====

<code asm>
@AuxInit port, settings
</code>

===== 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 |