Fluke 5790A, Руководство оператора

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5790A
Operators Manual
5-18
7 6 5 4 3 2 1 0
RID
RQS
MSS
ESB MAV EAV ISCB 0 0
RID Remote idle. Set to 1 when the remote interface is waiting for input.
RQS Requesting service. The RQS bit is set to 1 whenever bits ESB, MAV, EAV, or ISCB change from 0
to 1 and are enabled (1) in the SRE. When RQS is 1, the 5790A asserts the SRQ control line on
the IEEE-488 interface. You can do a serial poll to read this bit to see if the 5790A is the source of
an SRQ.
MSS Master summary status. Set to 1 whenever bits ESB, MAV, EAV, or ISCB are 1 and enabled (1) in
the SRE. Thi s bit can be read using the *STB? command in serial remote control in place of doing
a serial poll.
ESB Set to 1 when one or more enabled ESR bits are 1.
MAV Message available. The MAV bit is set to 1 whenever data is available in the 5790A's IEEE-488
interface output buffer.
EAV Error available. An error has occurred and an error is available to be read from the error queue by
using the ERR? query.
ISCB One or more enabled ISCR bits are 1.
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Figure 5-2. Status Byte and SRE Bit Definitions
Convert the contents of variables A and B into binary, and you can read the status of the
registers. For example if A is "32", its binary equivalent is: 00000000 00100000.
Therefore, bit 5 (CME) in the ESR is set (1) and the rest of the bits are reset (0). This
means that the 5790A tried to execute an incorrectly formed command.
By setting the bits in the ESE, you can mask (disable) the associated bits in the ESR. For
example, to prevent the occurrence of a command error from causing bit 5 (ESB) in the
serial poll status byte to go to 1, you can reset (to 0) bit 5 in the ESE register. The
following sample program accomplishes this by checking the status of the CME bit, then
toggling it if it is 1.
10 ! THIS PROGRAM RESETS BIT 5 (CME) IN THE ESE
20 PRINT @6,"*ESE 33" ! INITIAL ESE IS CME + OPC
30 GOSUB 100 ! GET AND PRINT INITIAL ESE
40 IF (A% AND 32%) THEN A% = A% - 32% ! CLEAR CME (BIT 5)
50 PRINT @6, "*ESE ";A% ! LOAD THE ESE WITH THE NEW VALUE
60 GOSUB 100 ! GET AND PRINT NEW ESE
70 END
100 PRINT @6, "*ESE?" ! ASK FOR THE ESE CONTENTS
110 INPUT @6, A% ! RETRIEVE THE REGISTER CONTENTS
120 PRINT "ESE = ";A%
130 RETURN