8 years, 7 months ago.

Serial Comms only works with reset

Due to uncontrollable circumstances, I'm unable to use the USB cord provided for serial communication between my mbed and PC. So, as a work around, I rigged up a Sparkfun shifter to allow me to communicate over serial pins 9 and 10 directly to my PC over a RS232 serial cord.

I've run a few of the example scripts (dimming an LED) with no problems, but run into issues when I try running my own script. I'm reading values off of a sensor, doing some math on the mbed, and then sending things to my PC for graphing. When I use PuTTY to display what the mbed is sending, more often than not I get gibberish. However, as soon as I press the reset button on the mbed my data starts coming across correctly. Similarly, when I run my matlab script, it keeps telling me that it's an "unsuccessful read" until I hit the reset with the script running. At this point it works for roughly 5 seconds before error-ing out. Does anyone know what might be causing this?

I'm very new to mbeds, but my best guess is that the data is somehow getting corrupted and when I reset the mbed it rights itself. I have no idea if this is the case, but I really need a way to fix this.