Problems debugging with LPCXresso 6 and LPCXpresso LPC812 board

[lpcware]

Content originally posted in LPCWare by ntipping on Wed Sep 25 07:23:30 MST 2013
Hi All,

I am having the infamous dropping out of the LPC-Link on (in this case) the LPC812 LPCXpresso board (Yes, that old chestnut).I have trauled the forums for solutions to the problem (which has been raised many times), but they all seem somewhat tenuous to me. And I have:

Tried a desktop running W7, a laptop running W8, several USB cables with and without a USB hub, and a separate 5V supply (which is at 5V) - all with no success. The link is always lost within a few operations.

I'm only running the example Blinky application, and have not managed to make a single change to it reliably before the link is lost. Some combination of disconnecting, powering the board down, powering the board up and reconnecting, or restarting LPCXpresso usually fixes it. I've also noticed that when it loses connection, it disappears in Device Manager. The only thing I've done beyond the plain vanilla install is change my Workspace to a 'hard' location on the 'C' drive (The default 'Documents' path seemed to result in the other commonly reported problem of include paths being reported as invalid), and also not allowing various bits of LPCXpresso from wanting access to the internet through my firewall (for some inexplicable reason).

I will try another cable when I can get one, but beyond that, it is either the board or just a general lack of robustness. Does anyone have a better understanding of the issues?

I'm in the process of deciding which ARM manufacturer to go with, and while I really do appreciate the free-to-low-cost nature of LPCXpresso, it's not helping the case much. By the way, I'm on a one-time login at the moment, because although I have changed my password several times and saved it, I don't seem to be able to log back in again (and the old one no longer works). Is there a time delay on updating passwords?

I know the above sounds like a winge, but if only this stuff was bullet proof, it would be immense. I really want it to work!

Best Regards,

Nick Tipping

[lpcware]

Content originally posted in LPCWare by ntipping on Wed Sep 25 09:55:57 MST 2013
Yes, good point. Having resoldered the crystal, I seem to be getting more reliable operation. Breakpoints seem to be working fine (Sometimes previously I was getting a warning trianle over the breakpoint marker suggesting that it couldn't be resolved). That seems to have stopped too. Fingers crossed, I'm up and running. Thanks for the rapid support.

Nick

[lpcware]

Content originally posted in LPCWare by TheFallGuy on Wed Sep 25 08:57:29 MST 2013
How about stopping a debug session before starting a new one (press the big red square in the debugger). The debugger won't find LPC-Link becuase it is being used by your original debug session.

[lpcware]

Content originally posted in LPCWare by ntipping on Wed Sep 25 08:39:03 MST 2013
Thanks for the prompt suggestion. I can't particularly see anything wrong with the connector (but can't rule it out). The ARM9 crystal did look a bit sus, so resoldered that, but to no avail. Same pattern - powered the board up, connected it, startes LPCXpresso, selected 'Debug Blinky', download succeeded, selected 'Run' 'Pause' a few times and all ok, paused and selected 'Debug Blinky' again and LPC-Link had gone walk-about.

Thanks again.

Nick

[lpcware]

Content originally posted in LPCWare by lpcxpresso-support on Wed Sep 25 07:47:00 MST 2013
If the LPC-Link is disappearing from Device Manager, then it sounds to me like you have a broken board. There is perhaps a problem with the USB connector on the board.