Fluke 5502A, Руководство оператора

Страница: 183 / 378

Remote Operation
Check 5502A Status
5
5-41
Programming the STB and SRE
If you reset (to 0) the bits in the SRE, you can mask (disable) associated bits in the serial
poll status byte. Bits set to 1 enable the associated bit in the serial poll status byte. The
subsequent sample BASIC program enables the Error Available (EAV) bit.
10 ! THIS PROGRAM SETS EAV IN THE SRE
20 PRINT @6,”*SRE 8” ! LOAD THE REGISTER
30 PRINT @6, “*SRE?” ! ASK FOR THE SRE CONTENTS
40 INPUT @6, A% ! RETRIEVE THE REGISTER CONTENTS
50 PRINT “SRE = “;A%
60 RETURN
The subsequent BASIC program gives an error and verifies the Serial Poll Status Byte.
Enable the EAV bit with the example above.
10 ! THIS PROGRAM GENERATES AN ERROR AND CHECKS IT
20 PRINT @6, “OUT 1300V” ! 1300V IS OUT OF 5502A RANGE
30 A% = SPL(6) ! DO A SERIAL POLL
40 IF ((A% AND 72%)=0%)THEN PRINT “EAV and RQS should have been set”
50 PRINT @6, “*STB?” ! RETRIEVE BYTE
60 INPUT @6, A%
70 IF ((A% AND 8%)=0%) THEN PRINT “EAV should have been set”
Event Status Register (ESR)
The Event Status Register is a two-byte register where the higher eight bits are 0 and the
lower eight bits represent different conditions of the Calibrator. The ESR is cleared (set
to 0) when you turn power on, and each time it is read.
Parameters are necessary for many of the remote commands. Incorrect use of parameters
can make command errors. When a command error occurs, bit CME (5) in the Event
Status Register (ESR) goes to 1 (if enabled in ESE register), and the error is recorded in
the error queue.
Event Status Enable (ESE) Register
A mask register called the Event Status Enable register (ESE) lets the controller enable or
mask (disable) each bit in the ESR. When a bit in the ESE is 1, the related bit in the ESR
is enabled. When an enabled bit in the ESR is 1, the ESB bit in the Serial Poll Status Byte
also goes to 1. The ESR bit stays 1 until the controller reads the ESR or does a device
clear, a selected device clear, or sends the reset or
*CLS
command to the Calibrator. The
ESE is cleared (set to 0) when the power is turned on.
Bit Assignments for the ESR and ESE
The bits in the Event Status Register (ESR) and Event Status Enable register (ESE) are
given as shown in Figure 5-10.