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

IEEE-488 Reference5.10.14 *STB? ⎯ status byte queryPurposeTo read the contents of the Status Byte Register.Format*STB?DescriptionThe *STB? query command is used to acquire the value (in decimal) of the Status Byte Register.The Status Byte Register is shown in Figure 5-17. The binary equivalent of the decimal valuedetermines which bits in the register are set. The set bits in this register define the operating statusof the Model 7002.When the *STB? query command is sent, the decimal value is placed in the Output Queue.When the Model 7002 is addressed to talk, the value is sent from the Output Queue to the computer.All bits, except Bit 6, in this register are set by other event registers and queues. Bit 6 sets whenone or more enabled conditions occur.The *STB? query command does not clear the status byte register. This register can only becleared by clearing the related registers and queues. Register and queue structure are explainedin paragraph 5.6.For example, for an acquired decimal value of 48, the binary equivalent is 00110000. This binaryvalue indicates that Bits 4 and 5 of the Status Byte Register are set.The bits of the Status Byte Register are described as follows:Bit 0 — Not used.Bit 1 — Not used.Bit 2, Error Available (EAV) ⎯ Set bit indicates that an error message is present in the ErrorQueue. The error message can be read using one of the following SCPI commands::SYSTem:ERRor?:STATus:QUEue?See paragraphs 5.17 and 5.16 for details.Bit 3,Questionable Summary Bit (QSB) ⎯ Set bit indicates that too many channels haveclosed.Bit 4, Message Available (MAV) ⎯ Set bit indicates that a message is present in the OutputQueue. The message is sent to the computer when the Model 7002 is addressed to talk.5-62