1-8
1
1.7
INDICATORS
Six LEDs that display the following conditions:
PWR - Indicates power on.
RDY - Indicates unit has passed self test.
TALK - Indicates unit has recognized its talk address.
LSTN - Indicates unit has recognized its listen address.
SRQ
- On when the RQS bit is set.
ERR
- On when ESR bits 2 thru 6 are set on.
When the 4899A is turned on, it performs an internal self test which takes
about 0.5 seconds. Only the PWR indicator is on during self test. At the
end of the self test the 4899A displays its current GPIB address by blinking
the front panel LEDs for one-half second. The GPIB address is the sum of
the binary bit weights. The LED bit weights are:
RDY
TALK
LSTN
SRQ
ERR
16
8
4
2
1
Any errors found during self test are indicated by a repeated blinking of the
error code pattern. Refer to paragraph 5.4 for a description of the selftest
errors and their possible causes.
During normal operation, the ERR LED indicates that there was a problem
with the GPIB command or with the Modbus communication. If the ERR
LED illuminates at power turn-on, it indicates that the unit has not been
calibrated since the memory was last initialized. Refer to paragraph 5.3.1
for directions on calibrating the unit.
Summary of Contents for 4809A
Page 5: ...ii This page left intentionally blank...
Page 51: ...2 30 2 This page left intentionally blank...
Page 89: ...4 8 4 This page intentionally left blank...
Page 99: ...5 10 5 This page left intentionally blank...
Page 125: ...A 26 A3 This page intentionally left blank...
Page 131: ...I Index 6 This page left intentionally blank...