KEPCO MAT 1/3 Rack - Manual (Page 36)

MAT 1/3 RACK/112404 3-5
mable Instruments (SCPI) or the Control Interface Intermediate Language (CIIL). Refer to the
Power Module Controller Operator’s Manual for details regarding SCPI and CIIL commands.
Communications with the MAT Power Modules are accomplished via a two-wire high speed
(375 KHz) bidirectional serial communications bus, called the Control Bus.
The Power Module Controller is designed with a microcomputer board containing a relatively
powerful CPU, 256K of RAM, programmable timers, priority interrupt circuits, an RS-232 input/
output interface port and ROM firmware (embedded software). A discrete fault line is designed
into the Power Module Controller to report catastrophic failures. Communications with an exter-
nal terminal are achieved via an RS-232 communications bus and related interface card.
Power for the microcomputer board of the TMA 4882-27 Power Module Controller is provided by
a wide range input Power Supply, Kepco Model MRW 150KV. The AC input voltage can range
from 95 Volts AC to 264 Volts AC, thereby eliminating the need for an input voltage selector.
The IEEE-488 GPIB implements a number of Interface Functions from the IEEE-488 protocol
(see the Power Module Controller Operator's Manual for details on these functions). The Power
Module Controller microcomputer continuously polls all the Power Modules (via the Power Mod-
ule microcontroller on Digital Card A3, see PAR. 4.25.3) on the high speed Control Bus for any
change in their Status conditions. A Status Monitor Interface Board is provided in the Power
Module Controller as an interface to the Host Computer for reporting catastrophic failures within
the Power Modules. If such an error is reported back to the Power Module Controller, the Host
Computer then sends a Device Clear Command to open the isolation relays and reset all the
Power Modules to zero. Following that, a Status command is sent to determine the nature of the
failure. In Data Mode the Power Module Controller sends or receives messages per the IEEE
488 GPIB protocol. The messages are Enabled when the Attention line goes high. A Handshake
cycle is performed for every ASCII character sent or received over the IEEE-488 GPIB.
3.5.2 MAT/TMA PC-27 SYSTEM
A Power Module Controller is available from Kepco that plugs directly into any DOS based com-
puter to control the Power Modules (up to twenty seven Modules daisy-chained to a single Con-
trol Bus) without the need for an IEEE 488 GPIB. The use of the TMA PC-27 allows the Power
Module Controller microcomputer board, the IEEE-488 GPIB interface input/output port and the
RS 232 interface input/output port to be bypassed.
The TMA PC-27 Software can be loaded into a DOS based computer either as a Terminate and
Stay (TSR) resident program, or as a stand-alone program. As a TSR it may be called from any
of the following languages TURBO C, QUICK C, POWER C, TURBO PASCAL, QUICK PAS-
CAL, QUICK BASIC and INTERPRETED BASIC.
With the TMA Software loaded, the MAT Power Modules may be programmed over the Control
Bus using CIIL or KPL (Kepco Programming Language). KPL is a simplified command set
based on CIIL. Catastrophic error messages will remain in memory until the cause of the failure
is determined and the error condition is corrected. Additional functions not supported by CIIL
have been included. A non-CIIL command, T0, calls for a noncatastrophic error message to be
erased when a command other than Status is sent. A T1 command causes noncatastrophic
error messages to be stacked in memory until interrogated by a Status command.
A programming language, referred to as KPL (Kepco Programming Language), is used to facili-
tate input/output operations for the TMA PC-27. It has embedded in it the software that sup-
ports the TMA PC-27 and is also compatible with National Instruments NI 488 DOS Handler for
the IEEE-488 GPIB.