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

IEEE-488 Reference5.10.4 *ESR? ⎯ event status register queryPurposeTo read the contents of the Standard Event Status Register and clear it.Format*ESR?DefaultsPower-up*CLS*RST:STATus:PRESetDCL, SDCClears registerClears registerNo effectNo effectNo effectDescriptionThis command is used to acquire the value (in decimal) of the Standard Event Status Register(see Figure 5-15). The binary equivalent of the returned decimal value determines which bits inthe register are set. When the *ESR? command is sent, the decimal value is placed in the OutputQueue and the Standard Event Status Register is cleared. When the Model 7002 is addressed totalk, the value in the Output Queue is sent to the computer.A set bit in this register indicates that a particular event has occurred. For example, for anacquired decimal value of 48, the binary equivalent is 0011 0000. For this binary value, bits B4and B5 of the Standard Event Status Register are set. These set bits indicate that a devicedependenterror and command error have occurred.The bits of the Standard Event Status Register are described as follows:Bit B0, Operation Complete (OPC) ⎯ Set bit indicates that all pending selected device operationsare completed and the Model 7002 is ready to accept new commands. This bit will onlyset in response to the *OPC? query command (see paragraph 5.10.7).Bit B1 ⎯ Not UsedBit B2, Query Error (QYE) ⎯ Set bit indicates that you attempted to read data from an emptyOutput Queue.Bit B3, Device-Dependent Error (DDE) ⎯ Set bit indicates that an instrument operation didnot execute properly due to some internal condition.Bit B4, Execution Error (EXE) ⎯ Set bit indicates that the Model 7002 detected an error whiletrying to execute a command.Bit B5, Command Error (CME) ⎯ Set bit indicates that a command error has occurred. Commanderrors include:1. IEEE-488.2 syntax error: Model 7002 received a message that does not follow the definedsyntax of the IEEE-488.2 standard.5-47