Using HDLC/LAP-D Protocol

Status and Error Messages

1

IO_DSBL

Terminal disabled

 

 

The terminal must be enabled before it will accept

 

 

write or control write requests.

11

IO_LONG_MSG

Message too long

 

 

Indicates one of the following errors:

 

 

• The packet length in the header is not zero.

 

 

• The control length in the header is not zero for a

 

 

CW_STATS or CW_REVCODE request.

 

 

• The control length in the header is greater than six

 

 

for a CW_TIMERS request.

12

IO_SHRT_MSG

Message too short

 

 

Indicates one of the following errors:

 

 

• The request length is less than four (too short to

 

 

contain the control write header).

 

 

• The control length in the header is less than six for

 

 

a CW_TIMERS request.

24

IO_BAD_CTL

Bad control function or format

 

 

Indicates one of the following errors:

• The control length in the header does not equal the request length plus four.

• The control code in the header contains a value

other than CW_STATS, CW_REVCODE or CW_TIMERS.

• The value specified for a timer resolution in a CW_TIMERS request is outside of the range zero to four.

Read Completion Status Codes

All receive completion messages will have the status IO_OK. Received messages that have errors are not returned by the protocol.

Chapter 3

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