HP 11i User Manual download pdf (Page 30)

30 Chapter3

Using HDLC/LAP-D Protocol

Request Specific Processing

Control Requests

All control writes to this protocol share a common format. The first four

bytesaredefinedasaheader:

Control Code

Defines the action to be taken by this request.

Control Length The length of the data for this control request. This data

immediately follows the header.

Packet Length Some protocols allow packet data (data to be transmitted

over the wire) to be passed to a control write following the

control request data. For this protocol, these two bytes

must be zero because the protocol does not allow packet

data within a control write.

This protocol allows the following Control Codes:

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Control Code Control Length

Packet Length

5 CW_STATS Send ST25L2STAT status message

This control write triggers the protocol to send a

ST25L2STAT status message. For the format of this

message, see the section on “Status and Error Messages”.

Control length must be zero.

6 CW_REVCODE Send ST25REVCD status message

This control write triggers the protocol to send a

ST25REVCD status message. For the format of this

message, see the section on “Status and Error Messages”.

Control length must be zero

1 2 ... 25 26 27 28 29 30 31 32 33 34 35 ... 53 54

No comments

HP 11i User Manual Page 30