Greetings,
I've been using CR1000s to control 2B Technologies (twobtech.com) ozone analyzers for some time. Recently, they have developed a capability for RS232 communications with their instruments. I've been successful communicating both ways with their instruments via TerraTerm, and I've used TerraTerm also to see what my CR1000 is transmitting. But, for some reason, the CR1000 and the instrument (Model 306 Calibration Source) will not communicate. Code used:
'Opens COM port and initiates pre-programmed z/s/p routine
SerialOpen(COMRS232,4800,0,0,240)
Delay(1,2,2)
SerialOut(COMRS232,"r","",0,10)
Delay(1,2,2)
SerialOut(COMRS232,"run step","",0,10)
Delay(1,2,2)
SerialClose(COMRS232)
I then have the following code to return the datalogger's RS232 port to normal comms parameters so I can link up normally for data download via PC200W:
SerialOpen(COMRS232,115200,0,0,240)
SerialClose(COMRS232)
I'd appreciate any ideas on what the problem might be, or even some details on the syntax of the commands (don't have the CRBasic manual available).
I've worked with the Ozone sensor but not the calibration source. I would suggest using the RS232 capabilities of the control ports on the logger to communicate with the analyzer and the calibration source. This would free up your RS232 port for normal communications. In the logger terminal emulator, you can "watch" the communications between the logger and the devices using the "W" command. Open the terminal window, hit a few returns till you get the CR1000 prompt. Enter "W", select the COM port you have the calibrator connected to, select a timeout, then Y to ASCII and you can watch your program work.
You can get the latest CR1000 manual here:
http://www.campbellsci.com/manuals
A discussion of the "serial watch" functionality Dave mentions is also included at the end of this great application paper covering serial I/O.
http://www.campbellsci.com/documents/technical-papers/serial.pdf
Thanks for the input...problem turned out to be a mismatch in pin locations; analyzer used pins 3 and 4 for Tx/Rx, CR1000 uses 2 and 3.
It would be odd if the analyzer used ppins 3 and 4 for RX/TX. Though it is not a standard, using pins 2 and 3 is rarely a practice deviated from. If it connects to your PC then the analyzer is using pins 2 and 3. More likely, you are reversing the pin count - remember the male and female are mirror images.