Campbell SDM-CVO4, Instruction Manual

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SDM-CVO4 4-Channel Current/Voltage Output Module
Else
WD_0_540 = WD_0_360
EndIf
' Scale the measurements for the SDM-CVO4 to output 0-10000 mV
WSOut = WS_ms*200 'WS: 0-50 m/s = 0-10000 mV
WDOut = WD_0_540 *18.59 'WD: 0-540 deg = 0-10000mV
TempOut= 100*(40) 'Temp: -40-60 deg C = 0-10000 mV
RHOut = RH *100 'RH: 0-100 % RH = 0-10000 mV
' Send mV outputs to SDM-CVO4 using the option to override the switch settings
SDMCVO4 (CVO4Output(),4,0,10)
NextScan
EndProg
6.3 SDMSpeed Instruction
Changes the rate that a CR800, CR850, CR1000, CR3000, or CR5000 uses to
clock the SDM data. Slowing down the clock rate may be necessary when
long cables lengths are used to connect the datalogger and SDM devices.
TABLE 6-1. Description of SDM Speed
Parameter
& Data Type
Enter
BitPeriod
Constant or
variable
The time per bit, in microseconds.
Initial Setting (default): 26.04 µS
Resolution: 8.68 µS
Min Setting: 8.68 µS
Max Setting: 2.2 mS
SDMSpeed(30) gives: 26.04 µS
SDMSpeed(k) gives: bit_rate = INT((k*72)/625) *
Resolution
When calculating SDMSpeed(k), the loggers round down to
the next higher bit.
6.4 Edlog Instruction 103
To allow full backwards compatibility with older dataloggers and operating
systems, the SDM-CVO4 is designed to work with the instruction supplied to
control the SDM-AO4 – Instruction 103. However, most datalogger manuals
and program editor help systems do not refer to the SDM-CVO4 in the
description of Instruction 103. Please see the details of use below to
understand the differences.
Instruction 103 is described in Table 6-2 and allows you to set four separate
output levels for one SDM-CVO4, or several output levels with multiple
SDM-CVO4s. Output levels are reset each time Instruction 103 is executed.
Instruction 103 was originally designed to take an input location range of
-5000 to +5000 and output this directly in mV when using the SDM-A04.
When used with the SDM-CVO4, the same range of values (±5000) in an input
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