Extended Status [+]; Control Handshake Lines [+] - Husky MP2500 Manual

Extended status [+]

Entry
Exit
Description

Control handshake lines [+]

Entry
Exit
Description
Chapter 25: INT 14H, Serial Port Handler
AH=22H
DX=port, non 0 (COM2)
AH=extended status
BX=number of characters in input buffer
CX=number of characters in output buffer
Used to obtain detailed error information from the
current protocol, including the status of the transmit
and receive buffers.
The standard protocols (NONE and XON/XOFF) return
the most recent error code in AH. For details of the
status information returned by other protocols, refer to
the protocol documentation.
Protocols will also return error information in the
RS232 status byte returned by the standard functions,
using the bits which most closely approximate the error
they need to report.
AH=23H
BH=line
BL=level
DX=port, 01H (COM2)
Returns nothing
Can be used to control the DTR and RTS handshake
output lines directly, for the port specified by DX. The
specified level remains latched until changed by use of
this function or normal communications handshaking.
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