Common Commands 12-13
Description
Use the *SRE command to program the Service Request Enable Register. Send this command
with the decimal equivalent of the binary value that determines the desired state (0 or 1) of each
bit in the register. This register is cleared on power-up.
This enable register is used along with the Status Byte Register to generate service requests
(SRQ). With a bit in the Service Request Enable Register set, an SRQ occurs when the
corresponding bit in the Status Byte Register is set by an appropriate event. For more
information on register structure, see the information presented earlier in this section.
The Service Request Enable Register is shown in Figure 12-3. Notice that the decimal weight
of each bit is included in the illustration. The sum of the decimal weights of the bits that you
wish to set is the value that is sent with the *SRE command. For example, to set the ESB and
MAV bits of the Service Request Enable Register, send the following command:
*SRE 48
Where: ESB (bit B5) = Decimal 32
MAV (bit B4) = Decimal 16
<NRf> = 48
The contents of the Service Request Enable Register can be read using the *SRE? query
command.
Figure 12-3
Service request enable register
B7 B6 B5
B4 B3
B2 B1
B0
(2 )
4
(2 )
5
1632
0/10/1
Bit Position
Event
Decimal Weighting
Value
Value: 1 = Enable Service
Request Event
0 = Disable (Mask)
Service Request Event
Events : OSB = Operation Summary Bit
ESB = Event Summary Bit
MAV = Message Available
QSB = Questionable Summary Bit
EAV = Error Available
MSB = Measurement Summary Bit
OSB ESB QSBMAV EAV MSB
(2 )
7
128
(2 )
3
8
(2 )
2
4
(2 )
0
1
0/1 0/10/10/1