Thruline RF Power Meter, Model 4421
21
SRQ
M
ask
(Mxx)
Function
Selectively masks status bits to prevent unwanted service requests.
Set xx to the sum of the binary values of the desired SRQ trigger bits.
For example, M12 would set the SRQ for both operation complete and underrange
(values 8 and 4). Set xx to “00” to never generate an SRQ.
Remarks
If a status bit is masked (bit set to 0), SRQs won’t be generated for that condition.
Table 12
SRQ Mask Bits
Status
(Ux)
Function
Reads a status word and returns the information as a string. Set x to:
“0” for machine status.
“1” for error status.
“2” for revision history.
Remarks
After sending the status command, a status word is sent the next time the unit is
addressed to talk. To ensure the correct status is transmitted, the status word should be
requested as soon as possible after the command is sent.
The format of the machine status word is shown in
Figure
9
. The default values are also shown.
Figure
9
Machine Status Word Format
Binary Value
Bit Number
Message
1
0 (LSB)
Error (IDDC, IDDCO, self-test fail)
2
1
Measurement overrange
4
2
Measurement underrange
8
3
Operation complete
4
Not Used
5
Not Used
6
Can’t mask
7 (MSB)
Not Used
Machine Status Word (U0) —
