SDM-CVO4 4-Channel Current/Voltage Output Module
6.3 CRBasic SDMCVO4 Instruction
This instruction is used to control the SDM-CVO4 four channel current/voltage
output device.
Syntax
SDMCVO4 ( CVO4Source, CVO4Reps, SDMAddress, CVO4Mode )
Remarks
This instruction controls the SDM-CVO4, which outputs a voltage or a current.
Internal jumpers are used to set the mode for the device, but the jumpers can be
overridden with the Mode parameter in this instruction.
CVO4Source The CVO4Source parameter is a variable array that holds the
values for the voltages (millivolts) or currents (microamps) that
will be output by each channel of the device (Source(1) sets
channel1, Source(2) sets channel2, etc.). When outputting a
voltage, the variable must be within the range of 0 to 10,000.
When outputting a current, the variable must be within the range
of 0 to 20,000.
CVO4Reps
The CVO4Reps parameter indicates the number of channels to set
to the defined voltage or current. Additional SDM-CVO4 devices
can be controlled by one SDMCVO4 instruction by assigning
them consecutive addresses and setting the CVO4Reps parameter
to a value equal to the total number of channels of all devices
(e.g., to set all four channels on two devices, set the CVO4Reps
parameter to 8).
If the CVO4Reps parameter is set to 0, power to the device will
be turned off.
SDMAddress The SDMAddress parameter defines the address of the SDM-
CVO4 which will be affected by this instruction. Valid SDM
addresses are 0 through 14. Address 15 is reserved for the
SDMTrigger instruction.
CRBasic dataloggers use base 10 when addressing SDM devices.
Edlog programmed dataloggers (e.g., CR10X, CR23X) used base 4
for addressing.
NOTE
CVO4Mode
The CVO4Mode determines what type of signal will be output by
the device. The options are:
Option
Description
0
Voltage output, use jumper settings (scale only)
1
Current output; use jumper settings (scale only)
10
Voltage output; override jumper setting
11
Current output; override jumper setting
The two override options (10 and 11) affect all of the channels of
all of the SDM-CVO4 devices being controlled by this
instruction. These two options override the hardware settings in
the device. Use of this mode takes approximately 2 milliseconds
additional time per device. When either of these options is used
you lose the flexibility of setting the output mode for each
channel individually. Additionally, subsequent programs sent to
the datalogger must also use an override mode or the power must
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