command. The value in the Parallel Poll Enable Register is ANDed with the Status Byte Register;
if the result is zero then the value of
The instrument must also be configured so that the value of
during a parallel poll operation. The instrument is configured by the controller sending a Parallel
Poll Configure command (PPC) followed by a Parallel Poll Enable command (PPE). The bits in
the PPE command are shown below:
bit 7 =
bit 6 =
bit 5 =
bit 4 =
bit 3 = Sense - sense of the response bit; 0 = low,
bit 2 =
bit 1 =
bit 0 =
Example. To return the RQS bit (bit 6 of the Status Byte Register) as a 1
when true and a 0 when false in bit position 1 in response to a
parallel poll operation send the following commands
The parallel poll response from the generator will then be 00H if RQS is 0 and 01H if RQS is 1.
During parallel poll response the DIO interface lines are resistively terminated (passive
termination). This allows multiple devices to share the same response bit position in either wired-
AND or wired-OR configuration, see IEEE 488.1 for more information.
Power on Settings
All remote control instrument settings are cleared at power up as shown in the following list. The
power on settings are also installed if the REMOTE/LOCAL switch is set to local.
Voltage set to 0V for 30V supplies and 4V for logic supplies.
Current set to 1mA for 30V supplies and 1A for logic supplies.
Electronic output switches are off.
*
*
*
*
*
Registers marked thus are specific to the GPIB section of theinstrument and are of limited
use in an ARC environment.
ist
X
don't care
1
1
Parallel poll enable
0
1 = high
?
?
bit position of the response
?
∗PRE 64
then PPC followed by 69H (PPE)
<pmt>,
Status Byte Register
Service Request Enable Register
Standard Event Status Register
Standard
Event
Register
Limit Event Status Register
(Then set to show new limit
status)
Limit Event Status Enable
Register
Execution Error Register
Query Error Register
Parallel Poll Enable Register
is 0 otherwise the value of
= 0
= 0
= 128 (pon bit
set)
Status
Enable
= 0
= 0
= 0
= 0
= 0
= 0
is 1.
ist
can be returned to the controller
ist
17