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

IEEE-488 ReferenceThe filter can be programmed for positive transitions (PTR),negative transitions (NTR) or both. When an event bit is programmedfor a positive transition, the event bit in the QuestionableEvent Register will set when the corresponding bitin the Questionable Condition Register changes from 0 to 1.Conversely, when programmed for a negative transition, thebit in the status register will set when the corresponding bitin the condition register changes from 1 to 0.Reading this register using the above SCPI command clearsthe register. The following list summarizes all operations thatwill clear the Questionable Event Registers:1. Cycling power.2. Sending the *CLS common command.3. Sending the :STATus:QUEStionable? query command.The individual bits of the transition filter registers can be setor cleared by using the following SCPI commands::STATus:QUEStionable:PTR :STATus:QUEStionable:NTR The transition filter registers can be read at any time by usingthe following SCPI query commands::STATus:QUEStionable:PTR?:STATus:QUEStionable:NTR?Reading a transition filter register using the above querycommands does not affect the contents of the register.Questionable Event Enable Register — This register isprogrammed by the user and serves as a mask for the QuestionableEvent Register. When Masked, a set bit in the QuestionableEvent Register will not set the QuestionableSummary Bit (QSB) in the Status Byte Register. Conversely,when unmasked, a set bit in the Questionable Event Registerwill set the QSB bit.A bit in the Questionable Event Register is masked when thecorresponding bit in the Questionable Event Enable Registeris cleared (0). When the masked bit of the QuestionableEvent Register sets, it is ANDed with the correspondingcleared bit in the Questionable Event Enable Register. Thelogic “0” output of the AND gate is applied to the input ofthe OR gate and thus, will not set the QSB bit in the StatusByte Register.The following operations will set (1) all the bits of the PTRregister and clear (0) all the bits of the NTR register:1. Cycling power.2. Sending the :STATus:PRESet command.3. Sending the :STATus:QUEStionable:PTR 65535 and:STATus:QUEStionable:NTR 0 commands.A bit in the Questionable Event Register is unmasked whenthe corresponding bit in the Questionable Event Enable Registeris set (1). When the unmasked bit of the QuestionableEvent Register sets, it is ANDed with the corresponding setbit in the Questionable Event Enable Register. The logic “1”output of the AND gate is applied to the input of the OR gateand thus, will set the QSB bit in the Status Byte Register.Questionable Event Register — This is a latched, read-onlyregister whose bits are set by the Questionable ConditionRegister and Transition Filter. Once a bit in this register is setit will remain set (latched) until the register is cleared by aspecific clearing operation. The bits of this register are logicallyANDed with the bits of the Questionable Event Registerand applied to an OR gate. The output of the OR gate isthe Questionable Summary Bit (QSB) of the Status ByteRegister. The following SCPI query command can be used toread the Questionable Event Register::STATus:QUEStionable:EVENt?The individual bits of the Questionable Event Enable Registercan be set or cleared by using the following SCPI command::STATus:QUEStionable:ENABle The following SCPI query command can be used to read theQuestionable Event Enable Register::STATus:QUEStionable:ENABle?5-20