HP 8642A Operation And Calibration Manual

Model 8642A/B
Operation
Overview
Reading the
Status Byte
C!caring the
~
STATUS BYTE
The 8642A/B Status Byte consists of one 8-bit byte which reflects Signal Generator
status. All 8 status bits are updated whether the Signal Generator is in local or remote
mode.
Each bit of the Status Byte monitors a partIcular aspect of the Signal Generator's
operation Table 3-7, HP-IB Status Byte Bit Deflllitions (on the following page), details
the operatlI1g conditions which are monitored by the 8642 Status Byte.
The Status Byte can either be used to cause a Service Request or simply be read to monitor
the Signal Generator's operating status
To read the Signal Generator's Status Byte, the controller must send the Serial Poll Enable
bus command and address the Signal Genera tor to talk. For example:
Program Stajpment (in BASIC)
10 S = SPOLL (719)
If the RQS bit is !lot set, the Status Byte will reflect the CUITellt status of the instrument.
If the RQS bit is set, the Status Byte will reflect the status of the instrument when the
RQS bit was first set (or \vhen the Status Byte was last read with RQS set). To actually get
the current status of the instrument, the Status Byte should be read again. Note that the
act of reading the Status Byte (alone) does not clear any status bits.
Status Byte If the instrument does not have an unresolved hardware error, the Status Byte will be
"cleared" by executing any of the following:
Sending Clear Status (CS).
Sending Instrument Preset (lP)
Sending Device Clear or Selected Device Clear.
S\vitching the Power from Standby to On
You can also clear the Status Byte by clearing the iadlvidual status blls. Refer to Table
3-7 on the following page.
NOTE
Bits 3 (Local/Remote) and 4 (Ready) are not affected by "clearing" the
Status Byte Tbey always output tbelr actual values
3-29

HP 8642A Specifications

General

Brand	HP
Model	8642A
Category	Inverter
Language	English