KEPCO BHK-MG 40W (Half Rack) Series - Manual (Page 58)

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BHK-1/2-MG 121313
3.3 REMOTE MODE PROGRAMMING USING SCPI COMMANDS VIA IEEE 488 (GPIB). BUS
BHK-MG Power Supplies may be programmed over a control bus using SCPI (Standard Com-
mands for Programmable Instruments). SCPI provides a common language conforming to IEEE
488.2 for instruments used in an automatic test system. The control bus used must be either the
IEEE 488 standard communication bus (General Purpose Interface Bus, GPIB). or the RS 232
Serial Bus described in PAR. 3.5. Refer to Table 2-1 for input/output signal allocations.) Most
power supply functions available from the keypad can be programmed via remote commands,
in addition to some that are not available from the keypad (e.g. triggering, and local lockout).
This section includes a discussion of GPIB bus protocols (PAR. 3.3.1), instructions for changing
the GPIB address (PAR. 3.3.3), a discussion of the VISA (Virtual Instrumentation Software
Architecture) driver supplied with the unit (PAR. 3.4), followed by a detailed explanation of SCPI
programming (PAR. 3.7)
3.3.1 IEEE 488 (GPIB) BUS PROTOCOL
Table 3-6 defines the interface capabilities of the BHK-MG 40W Power Supply (Talker/Listener)
relative to the IEEE 488 (GPIB) bus (reference document ANSI/IEEE Std 488: IEEE Standard Dig-
ital Interface for Programmable Instrumentation) communicating with a Host Computer—Controller
(Talker/Listener). Tables 3-7 and 3-8 define the messages sent to the BHK-MG, or received by
the BHK-MG, via the IEEE 488 bus in IEEE 488 command mode and IEEE 488 data mode,
respectively. These messages are enabled during the “handshake” cycle, with the BHK-MG
40W Power Supply operating as either a Talker or a Listener.
TABLE 3-6. IEEE 488 (GPIB) BUS INTERFACE FUNCTIONS
FUNCTION
SUBSET
SYMBOL
COMMENTS
Source Handshake SH1 Complete Capability (Interface can receive multiline messages)
Acceptor Handshake AH1 Complete Capability (Interface can receive multiline messages)
Talker T6
Basic talker, serial poll, unaddress if MLA (My Listen Address) (one-byte
address)
Listener L4 Basic listener, unaddress if MTA (My Talk Address) (one-byte address).
Service Request SR1
Complete Capability. The interface sets the SRQ line true if there is an
enabled service request condition.
Remote/Local RL1
Complete capability. Interface selects either local or remote information. In
local mode the BHK-MG executes front panel commands, but can be set to
remote mode via IEEE 488 bus. When in Remote mode all front panel keys
are disabled except LOCAL. LOCAL key can be disabled using keypad
lockout command (see Appendix B, PAR. B.82) so that only the controller
or a power on condition can restore Local mode.
Parallel Poll PP0 No Capability
Device Clear DC1
Complete Capability. BHK-MG accepts DCL (Device Clear) and SDC
(Selected Device Clear).
Device Trigger DT1 Respond to *TRG and trigger functions.
Controller C0 No Capability