IBM 1 Series - Adapter Hardware Description; Adapter Command Functions

The rate of transfer is determined by the speed with which the sending
device places each byte on the bus and the effective data rate at which the
slowest of all receivers accepts the data byte, up to a maximum
instantaneous data rate of 65K bytes per second. Data rate is largely
dependent upon the block size of the data transfered.
Adapter Hardware Description
The GPIB adapter is a single Series/1 I/O card, which provides
cycle-stealing controller capabilities for an instrumentation network. The
adapter may be plugged into any I/O position on a Series/1 processor
card file or the 4959 I/O expansion unit card file. Multiple GPIB adapters
may be installed on a Series/1 system, with each feature controlling a
different GPIB network of OEM devices.
Interconnection between the GPIB adapter and the first OEM device on
the interface is accomplished via a 4-meter (13.1-ft) cable (RPQ D02119),
which provides an IEEE Standard 488 24-pin stackable connector as the
user interface. Additional OEM devices are interconnected with 1-, 2-, and
4-meter (3.3-, 6.5-, and 13.1-ft) IEEE 488 cables, which are available
throughout the industry.
Adapter Command Functions
A-2
GA34-0033
The GPIB adapter utilizes the cycle-stealing architecture of the Series/1 to
provide a high-speed controller for a GPIB network. The feature accepts
commands from the Series/1 processor I/O channel and provides all
required interface protocol for those operations. There are four groups of
GPIB adapter commands:
e Bus-initialization commands
e Information-exchange commands
e Universal GPIB commands
¢ Polling and status commands
Figure A-2 shows the command groups, with a description for each
operation. All command acronyms used by the GPIB adapter relate to the
specific operation, as described in the IEEE standard.