User manual

Appendix C. HC2S3 Digital Communications
C-5
RH=RH_Str
TempC=TempC_Str
CallTable Table1
NextScan
EndProg
C.4 RS-485 Communications using an SDM-SIO1
Serial I/O Module
The HC2S3 can be interfaced to a CSI datalogger through an SDM-SIO1 Serial
I/O Module using the Rotronic E2-05XX-MOD RS485 cable as described
below.
The example program uses the SerialOpen instruction to configure the SDM-
SIO1 for RS-485 half duplex, “COMport 32” at 19200 baud, no parity, 1 stop
bit, and 8 data bits, and serial instructions to send the RDD command to get
temperature and relative humidity data from the probe.
Sensor Wiring:
E2-05XX-MOD Cable SDM-SIO1 CR1000
Blue Z
Red Y
Grey/Yellow G
Green 12V
Clear Ground
SDM-SIO1 Wiring:
SDM-SIO1 CR1000
C1 C1
C2 C2
C3 C3
G G
12V 12V
If the Rotronic cable includes brown and white wires (voltage
signals for temperature and humidity), CSI recommends “capping”
them with PN #27749 or equivalent insulated caps to prevent the
possibility of shorting.
NOTE