714PC

10.8 ERROR MESSAGES

Since the LBA-PC is pretty much of a black box and the GPIB is not much better we have included

descriptive error messages and other information to make debugging a little easier.

The LBA-PC maintains two output queues, the response output queue and the error message queue.

To enable the error message queue, you must send the ERR command with a parameter specifying

verbose error reporting.

The verbose parameter is optional and is a boolean with a value of 0 or 1 (i.e. false or true). The

default for the verbose parameter is 1 (true). When verbose error reporting is true then the LBA-PC

enables the error message queue.

When the error message queue is enabled and the LBA-PC detects an error then a text string

description is placed in the error message queue. The LBA-PC then sets the EMAV bit, bit 3, in the

Status Byte to indicate an error message is in the queue.

Perform a serial poll or use the *STB? command to read the status byte. If the EMAV bit is set, use the

:ERR? command to read the error message. The EMAV bit will be cleared when the error message

queue is empty.

There are three categories of errors, two of which are reported via the error message queue. The first

category of errors is remote command errors. These errors include command, execution, and range

errors originating directly from commands sent by the host to the LBA-PC.

Example of a category 1 error:

Host sends

:ERR(^END)

Host sends

:APP?(^END)

Host sends

*STB?(^END)

LBA-PC sends

STB

#H08(^END)

Host sends

:ERR?(^END)

LBA-PC sends

!!! unrecognized command ‘APP'(^END)

Operator’s Manual LBA-PC

206