help with pic - seems ok but FMS doesn't see it

[peter-fms]

I've constructed a pic interface (12c508) using instructions found on the web. After some debugging, when I check it with the ocilliscope, it appears to be putting out serial data...
(-10 to +10v) to pin 2 of the serial plug. The serial data looks to have start and stop bits and appropriate 8 bits in between but it's hard to really see clearly on the scope. The packets appear to start with FF and have 8 more bytes followed by a pause.

With my comm port set to 19200 8n1, FMS running fine and the controls set to PIC interface...FMS does not see the data.

any suggestions on why? What should I try next?

[Eric Brouwer]

You can try using terminal or any other comms software to check if your interface data is correct. On my web, you can also download PIC Interface test software under the Interfaces page. It supports both 19200 and 9600 baud interfaces.

What you see on the scope sounds fine to me, the interface uses FF for synchronising, followed by channel 1, channel 2, ... So the interface seems to be OK.

Did you set up your interface correct, including the coms port? Remember that you will have to recalibrate FMS with the new interface as well, and assing the channel/mappings.

[Steve Lewin]

[peter-fms]

[Mike Roberts]

[peter-fms]

Well I got the new transistors in and set up the circuit as shown. It all works OK now. Thanks for the help and WOW now that I can fly this thing I'm very impressed. Both with the quality and with all the work that has gone into it from the programmers and from you guys that sort out the electronics. Thanks.
-Peter-