Specifications

Remote Programming 4-19
DS360 Ultra Low Distortion Function Generator
Status Byte Definitions
The DS360 reports on its status by means of three status bytes: the Serial Poll
Byte, the Standard Status Byte and the DDS Status Byte.
Upon power on, the DS360 may either clear all of its status enable registers or
maintain them in the state they were in on power down . The *PSC command
determines which action will be taken.
The status bits are set to 1 when the event or state described in the tables below
has occured or is present.
Serial Poll Status Byte
Bit Name Set When
0 Mod Done No modify function in progress
1 Mod Enable Modify function enabled
2 User SRQ User sends a front panel SRQ
3 DDS An unmasked bit in DDS is set
4 MAV The gpib output queue non-empty
5 ESB An unmasked bit in ESB is set
6 RQS/MSS SRQ (service request) has occured
7 No Command
No unexecuted commands in the input queue
The DDS and ESB bits are set whenever any unmasked bit (a bit with the
corresponding bit in the byte enable register set) in their respective status
registers are set. Use DENA and *ESE commands to set the enable register bits.
The DDS and ESB bits are not cleared until ALL enabled status bits in DDS and
ESB status bytes are cleared (by reading the status bytes or using *CLS).
Using *STB? to Read the Serial Poll Status Byte
A bit in the Serial Poll Status Byte is NOT cleared by using *STB?. The bit stays
set as long as the status condition exists. This is true even for RQS. RQS will be
set whenever the same bit in the Serial Poll Status Byte AND Serial Poll enable
registers are set. This is independent of whether a serial poll has occured to clear
the service request.
Using Serial Poll
Except for SRQ, a bit in the Serial Poll Status Byte is NOT cleared by polling
the status byte.When reading the status byte using a serial poll, the RQS bit
signals that the DS360 is requesting service.The RQS bit will be set to 1 the first
time the DS360 is polled following the service request. The serial poll
automatically clears the service request. Subsequent serial polls will return RQS
cleared (0) until another service request occurs. Polling the status byte and
reading it with *STB? can return different values for RQS. When serial polled,
RQS indicates a service request has occured. When read with *STB?, RQS
indicates that an enabled status bit is set.