Measurement Computing Serial488/4 - Manual (Page 33)

Section 2 Getting Started
2.21
2.6.2 My Listen Address (MLA), My Secondary Address (MSA)
The Serial 488/4 is addressed to listen in one of tw o ways dependent
upon the addressing mode selected. When dual primary addressing mode
is selected, the Serial488/4 is addressed to listen upon receipt of ML A. If
secondary addressing mode is selected the Serial488/4 is addressed to
listen upon receipt of an MLA and MSA sequence.
When the Serial488/4 is addressed to listen on its command/status
address it accepts characters from the active talker and interprets these
characters as commands and command parameters. These commands are
fully explained in Section 3.
When the Serial488/4 is addressed to listen on a serial data address it
accepts data from the active talker and places this data into the appropriate
serial output buffer, to be transmitted verbatim.
2.6.3 Device Clear (DCL and SDC)
Device Clear resets the Serial488/4 to pow er on defaults and empties
all the serial input and output buffers. Any pending data and Service
Requests (SRQ), including the information they convey are lost.
2.6.4 Interface Clear (IFC)
IFC places the Serial488/4 in the Talker/Listener Idle State and clears
any pending request from service (SRQ). The condition which caused the
SRQ, however, remains unchanged.
2.6.5 Serial Poll Enable (SPE)
When Serial Poll E nabled, the Serial488/4 sets itself to respond to a
serial poll w ith its serial poll status byte if addressed to talk. When the
serial poll byte is accepted by the controller, any pending SRQs are cleared.