Model 7002Switch System Instruction Manual - Advanced Test ...

Front Panel OperationFor this test system, the Model 196 is configured for externaltriggering and the scan is configured as follows:Scan List = 1!1-1!10,Arm Layer:Arm Spacing = Immediate*Arm Count = 1*Arm Trigger Control = Acceptor*4.17 Trigger LinkThe Model 7002 has enhanced external triggering capabilitiesusing the Trigger Link. The Trigger Link has six lines allowingup to six instruments to be controlled over this triggerbus. The 8-pin micro DIN sockets used for the Trigger Linkare shown in Figure 4-21.Scan Layer:Scan Spacing = Immediate*Number of Scans = 1Scan Trigger Control = Acceptor*Channel Layer:Channel Spacing = ExternalNumber of Channels = Use Scan List Length*Channel Trigger Control = Source*TRIGGERLINKDIGITAL I/OINOUT* Indicates that the setting is the RESET (and factory) default condition.Notice that Channel Trigger Control is set for Source. Withthis selection, scan operation will initially bypass the needfor an external trigger to close the first channel. Since armspacing and scan spacing are set for Immediate, the scan willstart immediately as soon as the scanner is taken out of theidle state by pressing the STEP key.Figure 4-21Trigger link connectorsNOTEWhen the front panel STEP key is pressed, the scanner willarm and close the first channel. After Channel 1!1 settles(channel ready), a trigger is sent from Channel Ready of theModel 7002 to External Trigger Input of the Model 196 totrigger a measurement of DUT #1. After the Model 196 completesthe measurement, it will output a trigger from VoltmeterComplete Output to External Trigger input of the Model7002, which closes the next channel. After Channel 1!2 settles,a trigger is sent to the Model 196 to trigger a measurementof DUT #2. When the measurement is completed, atrigger is sent to the Model 7002 to close the next channel.After this channel settles, a trigger is sent to the DMM totrigger a measurement. This process continues until all 10channels are scanned and measured. The data store of theModel 196 could be used to store the measurements as theyoccur.The two rear panel Trigger Link connectorsare actually connected in parallel toeach other. Thus, the IN and OUT labelsare a misnomer. It does not matter whichconnector you use when connecting theTrigger Link to another instrument.In general, Trigger Link input triggers to the Model 7002 areused to control scan operation. In order for the Model 7002to respond to Trigger Link compatible triggers, the appropriatelayers of the scan must be properly programmed. For example,if you want Trigger Link input triggers to control thechannel scan process, you must program Channel Spacingfor TRIGLINK trigger events. Typically, a Trigger Link outputtrigger from the Model 7002 would be used to trigger anotherinstrument to measure the currently selected channel.4-59