Specifications

Section 7. Measurement Instructions
Parameter
& Data Type
Enter
9 Flush converted data buffer.
66 Send single-byte data to datalogger.
67 Get return code.
320 Send byte data to SDM-SIO4.
321 Execute command line command.
1024 Send string to SIO4.
1025 Transmit a byte.
1026 Serial port status.
1027 Manual handshake mode.
2049 Communication parameters.
2054 Set up receive filter.
2304 Transmit string and/or data to device (formatter/filter).
2305 Transmit bytes.
Param1
Param1 is the first parameter that should be passed on to the SIO4 for the
selected Command. Refer to the SDM-SIO4 manual for details.
Param2
Param2 is the second parameter that should be passed on to the SIO4 for the
selected Command. Refer to the SDM-SIO4 manual for details.
ValuesPerRep
The ValuesPerRep parameter is the number of values to be sent or received
from each SIO4 each time this instruction is performed.
Mult, Offset
These parameters are the multiplier and offset with which to scale the values
received by the datalogger from the SIO4.
SDMSpeed (BitPeriod)
Changes the rate that the CR3000 uses to clock the SDM data. Slowing down
the clock rate may be necessary when long cables lengths are used to connect
the CR3000 and SDM devices.
Parameter
& Data Type
Enter
BitPeriod
Constant or
variable
The time per bit, in microseconds.
Initial Setting (default): 26.04 µS
Resolution: 4.34 µS
Min Setting: 8.68 µS
Max Setting: 2.2 mS
SDMSpeed(30) gives: 26.04 µS
SDMSpeed(k) gives: bit_rate = INT((k*144)/625) * Resolution
When calculating SDMSpeed(k), the loggers round down to the next higher
bit rate.
SDMSW8A (Dest, Reps, SDMAddress, FunctOp, SW8AStartChan, Mult,
Offset)
The SW8A instruction is used to control the SDM-SW8A Eight-Channel
Switch Closure module, and store the results of its measurements to a variable
array.
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