Multiple EI1050 temp/humidity sensors

[JohanKarlsson]

I am running one EI1050 perfectly, but two does not work I am connecting IO2 of the Labjack U12 to the first sensors enable and IO3 to the second sensors enable but dacfactory does not select them correctly, I have extrapolated info on using channel 0 and 1 and tries to use channel 2 and 3 for the second sensor is this correct if not how do I manage to read many sensors?? The testprogram that comes with the LJ works perfectly with multiple sensors.

/Johan

[AzeoTech]

The U12 only has a single SHT port, which is done using IO0 and IO1. If you want to plug in multiple EI1050's, you have to plug them all into IO0 and IO1 in parallel. You then need to use the Enable line on the EI1050 and another digital line to enable each one, making sure you don't enable more than one at once. Because it appears as a single input in DAQFactory, you are going to have to do a little script to get it to work. Lets say your EI1050 input (the special IO type) is called RawTemp and RawRH, and your digital out that enables the two probes is Enable1 and Enable2.

1) create four new channels called Temp1, Temp2, RH1, and RH2. Device type Test, D to A, Channels 0-3.

2) Set the timing for the RawTemp and RawRH channels to 0

3) Create a sequence to poll the two probes. I'll assume once a second:

while(1)
   enable1 = 1
   enable2 = 0
   read(RawTemp)
   temp1.addvalue(rawtemp[0])
   rh1.addvalue(rawRh[0])
   enable1 = 0
   enable2 = 1
   read(RawTemp)
   temp2.addvalue(rawtemp[0])
   rh2.addvalue(rawRh[0])
   delay(1)
endwhile

Run the sequence to start polling.