Hello. Thanks for looking in on my questions. Let me first describe what I am trying to accomplish. I am building a telemetry system for a radio controlled helicopter. The system will include an onboard unit to sample data and transmit it to my laptop. Labview will be the interface for the user: a virtual instrument cluster with gauges, etc showing the status of the aircraft. The onboard system is a PIC microcontroller. It is sampling data from four sensors (temp, RPM, Acceleration,Altitude). The data is then sent out serial, rs232, to my computer.
I have controll over what the microcontroller trasmits, so:
Is there a certain way I should format the data so that my life is easier?
Currently, I am sending a letter to signify the data point (T) and then the data (69.02) . The serial stream looks like ...T69.88R100T69.97R120..... (Only two data shown for simplicity) The stream never stops as the microcontroller is set into a loop and samples and transmits. I am able to read in the data using the measurement and automation explorer, but when I try to use the I/O Assistant, it does seem to read the data and drops a timeout error. The error says "timeout before completion". I am imagining that the I/O assistant is having problems deciding where the string begins and ends. Thus, my next question,
Do I need an end of transmission identifier in the stream (/r/n)?
I have all of the serial parameters matched up(baud, parity, etc). I have created a vi that runs to some extent using VISA operations(I/O, Bytes at port.vi, VISA Read, split string, etc). It only works right on step by step mode. Once I try to run it normally, it seems like none of the VISA operators are working right. Essentially, the string does not seem to get passed through the VI. I think I have a good idea of what to do with the data once I get it coming in correctly. It just seems like what I have set up is ghetto and simply doesnt work right. Other details, I am not using a DAQ, as they cost a fortune. I have an rs232 to USB adapter. It essentially emulates a serial port. It seems to work fine as I am able to read in data in a Measurement and Automation explorer VISA session. Let me know if you have some advice. Thanks for reading. Jeremiah.