Int 14H [PC] [AT] [PS/2] Function 02H Read character from communications port

Reads a character from the specified serial communications port, also returning the port's status.

Call with:

AH = 02H

DX = communications port number (0 = COM1, 1 = COM2, etc.)

Returns:

If function successful

AH bit 7 = 0

AH bits 0—6 = status

Bit Significance (if set)

1 overrun error detected

2 parity error detected

3 framing error detected

4 break detected

AL = character

If function unsuccessful (timed-out)

AH bit 7 = 1