HIGH SPEED IEEE 488 BUS INTERFACE SYSTEM AND METHOD

摘要

A modified IEEE 488.1 bus (104) interface (100-A, 100-B) increases, by as much as a factor of eight, the rate at which inter-instrument data transfers can be performed. The bus interface state machines (142, 144, 146, 148, 150, 160) presented in the ANSI/IEEE Std 488.1-1987 have been modified so that if all the devices (106) involved in a particular date transfer are equipped to handle high speed data transfers, then a modified data transmission methodology is used so as to enable multiline messages to be transmitted at a higher speed than would otherwise be possible. If any of the devices (106) involved in a particular data transfer does not have an interface equipped to handle high speed data transfers, this condition is automatically detected by the other interfaces with high speed capability, and then the standard data transmission methodology is used. The high speed data transmission mode is totally transparent to the controller (102, 120) software in that it does not require any changes to the controller (102, 120) software nor to the device drivers and device (106) application programs.