Example: Making Multiple ScansExample: Making Continuous Scans

The ARM:COUNt <number> command selects multiple scanning cycles for switchboxes with non-downloaded scans. It does not apply when the TRIGger:SOURce is DBUS or IMMediate.

Add the command before the SCAN <channel_list> in the first program example in this section. When the last channel in a channel list is closed, the pointer is reset back to the beginning of the channel list. The next trigger opens the last channel and closes the first one. This continues for the specified number of cycles.

59OUTPUT 70914;"ARM:COUN 10" !Enables 10 scanning cycles

60OUTPUT 70914;"SCAN (@100:215)"!Sets scan list

80 FOR I = 1 TO 320

The INITiate:CONTinuous ON command selects continuous scanning cycles (INIT:CONT OFF disables continuous scanning cycles). Add the command to the first program example in this section, as follows:

59OUTPUT 70914;"INIT:CONT ON" !Enables continuous scanning cycles

60OUTPUT 70914;"SCAN (@100:215)"!Sets scan list

80 FOR I = 1 TO X

!Set the number of measurements

 

desired

Comments Scanning consists of six steps:

∙Connecting the multimeter to the switchbox

∙Selecting the SCAN:MODE

∙Selecting the SCAN:PORT

∙Selecting the TRIGger:SOURce

∙Specifying the SCAN <channel_list>

∙Starting the scan (INIT or TRIG[:IMMediate])

Downloading a Scan List

The FET Multiplexer Module is primarily designed to be used as a high-speed scanning switchbox or scanning voltmeter. To enable it to make 100,000 connections per second, the SCAN <channel_list> scanning list is downloaded into RAM on the module. This download takes place automatically when you use TRIGger:SOURce DBUS or TRIGger:SOURce IMM. For a multiple-module switchbox, the entire scanning list is downloaded to each module. The channels are advanced to the next channel in the channel list without any direct intervention by the mainframe CPU during the scan.

The scan list is not downloaded for a switchbox or scanning voltmeter that combines both FET and relay multiplexer modules, or for TRIGger:SOURce BUS EXT HOLD. The channel closings are controlled by the mainframe CPU. Also, the ARM:COUNt <number> command does not apply to downloaded scan lists. You can use INITiate:CONTinuous ON for continuous scanning with downloaded scan lists.

Chapter 3

Using the HP E1351A/53A FET Multiplexer Modules 39