Mega 2560 not being recognized?

Board has been working. Now the "RX", 'TX" and "L" leds stay lit (even with external power supply) and I'm getting the following error messages:

avrdude: stk500v2_setparm(): failed to set parameter 0x9e
avrdude: stk500v2_command(): unknown status 0xc8
avrdude: initialization failed, rc=-1
         Double check connections and try again, or use -F to override
         this check.

avrdude: stk500v2_command(): unknown status 0x01
avrdude: stk500v2_disable(): failed to leave programming mode

I've swapped out the USB cables and switched ports.

dandrum:
Board has been working. Now the "RX", 'TX" and "L" leds stay lit (even with external power supply) and I'm getting the following error messages:

avrdude: stk500v2_setparm(): failed to set parameter 0x9e

avrdude: stk500v2_command(): unknown status 0xc8
avrdude: initialization failed, rc=-1
        Double check connections and try again, or use -F to override
        this check.

avrdude: stk500v2_command(): unknown status 0x01
avrdude: stk500v2_disable(): failed to leave programming mode




I've swapped out the USB cables and switched ports.

You are not alone...suggest going to the troubleshooting thread as it seems a few folks are having issues with 1.6.6 and boards and sketches not playing nice anymore.

I removed 1.6.6 and went back to 1.6.5 but you may also have to do some other clean ups (registry clean and such) before you put 1.6.5 back in.

Thanks for the info.

Ballscrewbob:
You are not alone...suggest going to the troubleshooting thread as it seems a few folks are having issues with 1.6.6 and boards and sketches not playing nice anymore.

I removed 1.6.6 and went back to 1.6.5 but you may also have to do some other clean ups (registry clean and such) before you put 1.6.5 back in.

1). I thought this WAS the troubleshooting thread ... is there another?
2). I think the problem is on the Mega board itself, in that the RX and TX lights are staying on constantly.

Have I fried the board? If so, can it be fixed - like by re-loading the boot routine?

dandrum:
Thanks for the info.
1). I thought this WAS the troubleshooting thread ... is there another?
2). I think the problem is on the Mega board itself, in that the RX and TX lights are staying on constantly.

Have I fried the board? If so, can it be fixed - like by re-loading the boot routine?

I thought I had a couple of dead boards that no longer worked after upgrading to 1.6.6
Even after going back to 1.6.5 they were still not accepting sketches. even though one had hardly been used.

I tried to reload the bootloader but they both fail.
Tried to upload bootloader with a tiny usb and it says it worked but they still don't accept sketches.

I can however still upload with the tinyusb and the sketches still run just fine.
If you have one then its worth a shot. Takes a few moments longer that's all.

Which IDE are you using ? as it seems a lot of people have had issues since upgrading to the latest one.

There is one UNO in my collection that by rights should have been dead a long time ago and despite my abuse it still works 100% They are quite resilient little buggers :grinning:

Try the loopback test to start - make sure the USB/Serial interface is still good.