bit 6
=
1
bit 5
=
1
Parallel poll enable
bit 4
=
0
bit 3
=
Sense sense of the response bit; 0 = low,
1 = high
bit 2
=
?
bit 1
=
?
bit position of the response
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
∗
PRE 64
<pmt>,
then PPC followed by 69H (PPE)
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
The following instrument status values are set at power on:
Status Byte Register
= 0
∗
Service Request Enable Register = 0
Standard Event Status Register
= 128 (pon bit
set)
∗
Standard Event Status Enable
Register
= 0
Execution Error Register
= 0
Query Error Register
= 0
∗
Parallel Poll Enable Register
= 0
∗
Registers marked thus are specific to the GPIB section of the instrument and are of limited use
in an ARC environment.
The instrument will be in local state with the keyboard active.
The instrument parameters at power on are determined on the POWER ON SETTING menu. If
restore last setup
or
recall store no. nn
has been set and a defined state is
required by the controller at start up then the command
∗
RST should be used to load the system
defaults.
If for any reason an error is detected at power up in the non-volatile ram a warning will be issued
and all settings will be returned to their default states as for a
∗
RST command.
Status Reporting
This section describes the complete status model of the instrument. Note that some registers are
specific to the GPIB section of the instrument and are of limited use in an ARC environment.
67