Instruction manual

This is the full model number of the BOS/S supply, including its serial number.
“?S” will return the last command string sent to the BOS/S controller. This can be
useful for debugging command sequences or verifying correct command reception.
6.5 MEASUREMENT COMMANDS
The BOS/S controller is capable of measuring the output voltage and output current of
the power supply. The optional A/D converter will provide either 16-bit or 12-bit
resolution. The readback message is returned as a measure of Volts, Amps, or for
fastest operation as simply the hexadecimal output of the A/D converter. The
conversion rate of the A/D is very fast however, and hex readback will usually not be
needed. The length of the returned message is determined by the setting of the
BACKTALK bit (see above).
The measurement commands are as follows:
“Measure V” = “MV” = measure output voltage and return result in Volts format.
“Measure V heX” = MVX” = measure output voltage and return result in hex format.
“Measure I” = “MI” = measure output current and return result in hex format.
“Measure I heX” = MIX” = measure output current and return in hex format.
These commands may be explicitly spelled out in the command string sent to the
BOS/S controller, but only those letters that are capitalized are actually needed. The
rest are ignored.
Assuming a 10 Volt, 20 Amp BOS/S supply at 10 Volts and -20 Amps, the following
messages would be returned using the following commands:
“MV” will put one of the following messages in the output buffer:
“Voltage = +10.000 Volts or “+10.000”
“MVX” will put on of the following messages in the output buffer”
“Voltage = ffff” or “ffff”
“MI” will put one of the following messages in the output buffer:
“Current = -20.000 Amps” or “-20.000”
“MIX” will put on of the following messages in the output buffer:
“Current = 0000” or “0000”
Note the value of the hex string. The A/D operates in an offset binary fashion:
-Full scale = 0000 hex
Zero = 7fff hex
+Full scale = ffff hex
6.6 CONTROL CHANNEL PROGRAMMING
The control channel is selected using the “SV” or “SI” commands to select either
voltage or current control for the BOS/S. The control channel has a resolution of
16-bits. There are several methods available to program the control channel. These
are:
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83-469-001 Rev. B