Anritsu MT9812B, Operation Manual, Page: 98 / 144

Section 5 Remote Control
5-30
5.6 Enabling the SRQ
Enabling the SRQ allows a summary message in the status byte register to be
selected in response to a service request. The service request enable (SRE) regis-
ter shown below can be used to select a summary message.
Bits of the service request enable register correspond to the bits of the status byte
(STB) register. When 1 is set in a status byte bit corresponding to a significant bit
of the service request enable register, the devices sets the RQS bit to 1 and issues
a service request to the controller. For example, when bit 4 of the service request
enable register is set (enabled) in advance, a service request can be issued to the
controller each time the MAV bit is set to 1 (if the output queue has data).
Logical OR
Service Request
Generation
Not used
ESB
MAV
ESB (ERROR)
ESB (END)
ESB (Not used)
Not used
7
5
4
3
2
1
0
7
5
4
3
2
1
0
&
&
&
&
&
&
&
Status Byte (STB) Register Service Request Enable (SRE) Register
MSS 6 RQS
disabled=0, enabled=128 (2 7 )
Not used
disabled=0, enabled=32 (2 5 )
disabled=0, enabled=16 (2
4
)
disabled=0, enabled=8 (2 3 )
disabled=0, enabled=4 (2 2 )
disabled=0, enabled=2 (2 1 )
disabled=0, enabled=1 (2 0 )
Status summary message
(1) Reading the service request enable register
service request enable register contents can be read using an
∗
SRE? com-
mon inquiry. The response message to this query is <NR1 NUMERIC RE-
SPONSE DATA>, an integer ranging from 0 to 255. It is a total of values of
the service request enable register. Service request enable register bits 0 to
5 and 7 are assigned weights 1, 2, 4, 8, 16, 32, and 128, respectively. Un-
used bit 6 must always be 0.
(2) Updating the service request enable register
The service request enable register is written using an
∗
SRE common com-
mand. The
∗
SRE common instruction is followed by a <DECIMAL NU-
MERIC PROGRAM DATA> element. <DECIMAL NUMERIC PRO-
GRAM DATA> is rounded to an integer. It is represented in binary nota-
tion using a base 2, indicating the total of values of service request enable
register bits (weight value). When the value of this bit is 1, it indicates the
enabled state. When the value of this bit is 0, it indicates the disabled state.
The value of bit 6 must always be ignored.