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LaunchPad Linux Serial Driver, Unstable ...?

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I had the temp demo talking perfectly to the Python data logger via GnuPlot on Ubuntu Lucid.


All of sudden the comport stopped working and that was that. Seen it on two computers...


Any suggestions/ideas/remedies?


Launchpad Rocks!



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its realy hard to say whats going on with your com port

on Karmic koala my launchpad will send data all day long with out stopping, but i use minicomm and a log file for my data logging if i need it


lets start with a few questions

will it start working after a powercycle or rebooting the PC?

have you tried something like minicom or other terminal to view the data in real time?



dmsg or any other logs would also help as bluehash has asked.

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Gee, thanks every body for the input!


Here's the relevant (I hope) section of dmesg output:


DUMP FOLLOWS ----------------------------------------------------------


[23309.799838] udev: starting version 151

[23444.408958] usb 2-1: new full speed USB device using uhci_hcd and address 4

[23444.640260] usb 2-1: configuration #1 chosen from 1 choice

[23445.017985] usbcore: registered new interface driver hiddev

[23465.185229] /build/buildd/linux-2.6.32/drivers/hid/usbhid/hid-core.c: usb_submit_urb(ctrl) failed

[23465.197849] generic-usb 0003:0451:F432.0001: timeout initializing reports

[23465.198791] generic-usb 0003:0451:F432.0001: hiddev96,hidraw0: USB HID v1.01 Device [Texas Instruments Texas Instruments MSP-FET430UIF] on usb-0000:02:00.0-1/input1

[23465.198823] cdc_acm 2-1:1.0: This device cannot do calls on its own. It is not a modem.

[23465.198891] cdc_acm 2-1:1.0: No union descriptor, testing for castrated device

[23465.198924] cdc_acm 2-1:1.0: ttyACM0: USB ACM device

[23465.198949] usbcore: registered new interface driver usbhid

[23465.199268] usbhid: v2.6:USB HID core driver

[23465.219966] usbcore: registered new interface driver cdc_acm

[23465.219970] cdc_acm: v0.26:USB Abstract Control Model driver for USB modems and ISDN adapters


DUMP ENDS ----------------


This is when it works OK, need to get organized see a failure, and then compare...


I have half a dozen of these boards, I will try first


1. Another board


2. A better quality cable, this one is a little touchy.



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I get that occasionally here. Shut down your comms software, pull out the USB cable, reattach and restart. It'll take a minute or two for the port to come back up. Make sure the software on the launchpad configures the RX pin to input and leaves the TX pin high when idle, otherwise cdc-acm will refuse to recognise the UART.

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Thanks moonshadow ... I may have been bringing the software back up with the board in an carelessly undefined state.


See attached run last PM. My setback thermostat working just as advertised.



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