Detecting Error Conditions; Using Interrupts With Error Checking; Analog Bus; 2-Wire Resistance Measurements - Agilent Technologies E8462A User Manual

Detecting Error Conditions

There are two general approaches to error checking. The simplest, but most
time consuming, is to ask the instrument whether there are errors at every
step of the switching process. This is called "polling" and is illustrated in the
two previous program examples.
Using Interrupts
The second approach involves the use of interrupts. In this approach, the
program monitors the Multiplexer's Standard Event Status Register for an
With Error
error condition. If no errors occur, the Multiplexer functions as
Checking
programmed. If errors do occur, the Multiplexer interrupts the computer,
and the error codes and messages are read from the error queue.

Analog Bus

[ROUTe:]SCAN:MODE RES sets the scanning mode to 2-wire resistance
measurements. The current source from the ohmmeter to the unknown
2-Wire Resistance
resistance is supplied over analog bus lines H2 and L2. The RES mode
Measurements
closes Tree relays T9 and T2 which connect H2 to H1 and L2 to L1. This
configuration allows H2 and L2 to source the current through the unknown
resistance and H1 and L1 to sense the voltage and make the resistance
measurement. You must make this connection manually if you use the
FUNCtion mode NONE or register program the multiplexer and desire
2-wire ohms measurements.
Using the Multiplexer 53