Data and Command Messages

From GPIB Analyzer

Data and Command Messages

Eight data lines, DIO1 through DIO8, carry both data messages and command messages. All commands and most data use the 7-bit ASCII or ISO code set, in which case the eighth bit, DIO8, is either not used or used for parity. Command messages are sent with the ATN line asserted; data messages are sent with the ATN line unasserted.