User`s manual

Agilent E1330B Digital I/O Module Register Information 119
Appendix B
A Register-Based Output Algorithm
The following algorithm describes the procedure you would use to program
the registers to transmit a byte of data to a peripheral. The algorithm follows
a flag-driven output procedure initiated by the computer. The computer polls
the Digital I/O module to see if the data has been accepted by the peripheral
by checking the Port Transfer/Control Register, bit 0 (referred to as the
acknowledge flag - hence, the name of flag-driven). Once the flag is TRUE
the computer can output new data to the port. The actual path followed by
the peripheral and the Digital I/O module to set this bit is controlled by the
handshake mode you select.