massive problems with LPC-LINK

[lpcware]

Content originally posted in LPCWare by navman on Mon Jul 11 07:45:38 MST 2011
Hi,
I've been using the LPC-LINK with LPC1768 target (we purchased half a dozen such boards for various projects). We have been planning to use it with the LPCxpresso. But the problems so far have been massive and it seems we are spending more time with the problems using the tools rather than writing code. The problems are random but persistent. The problems we see are:
1) When trying to "debug" the code, we get an error saying "crt_emu_cm3_nxp.exe has stopped working". We hit close.
2)"Initializing LPC-link window" opens and stays forever. Meanwhile, in the system tray, a message "USB device not recognized" keeps on popping up and going off. I have to kill the lpcxpresso and DFUAPP to make it go away.
3) The debugger works sometimes when the system is restarted with the LPC-LINK connected
4) Sometimes we get a window suggesting that "No emulator or board available".
5) Sometimes it is a "failed on connect not connected to emulator"

So we are having problems 90% of the time and only 10% of the time we are able to write some code.

We are using Windows Vista (up to date) and when the device is plugged in, it shows up as a "USB device with DFU capabilites" in device manager.

Can Code Red support please suggest if something wrong with our system or do we need to keep fighting the device?

[lpcware]

Content originally posted in LPCWare by Rob65 on Wed Jul 13 03:39:28 MST 2011

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Quote: navman
It seem we have been able to trace the problems to an unshielded USB cable being used to power the board.

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Unshielded cables are low speed only.
High-/Full-speed cables require a shielding according to the USB specification (see usb_20.pdf, page 92 & 102).

Use only high-/full-speed cables with the LPCXpresso boards.
I thought (and that idea is confirmed by the usb spec.) that low speed cables must have a fixed connection to the device. An unshielded USB cable with A and B connectors is not a proper USB cable (and is not allowed to carry the USB logo ...).
Use only cables that are marked "USB high speed" to prevent any problems.

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Quote:

Once we replaced it with a shielded USB cables, things are much better. Although, we still have sporadic problems where we have to unplug and replug the USB cable or even restart the PC sometimes to get the LPC link recognized.

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Sound like you are having a general problem with your setup.
Verify the power connections to your target board, what kind of power supply do you use, is it connected to the same power outlet as your PC, are you powering your application via the 3.3V output from the LPCXpresso module (i.e. the 3.3V regulator from the LPC-Link module) ?
[B]Is all your equipment properly grounded at one point?[/B] Is your PC connected to a power outlet with an earth connection?

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Quote:

After much reading the posts, it seems most of these problems occur because the LPCxpresso IDE tries to reboot & change the driver for the LPC link. If Codered can build the LPC link firmware so this changing of drivers is not necessary (or atleast user can change depending on the need), then things will be much faster & less problematic. Is this possible Codered?

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The LPC-Link module contains an lpc3154 and it uses DFU to download the driver after applying power the first time. Just make sure that you always have power to your LPC-Link module, then the LPC-Link only reboots once.

Again: if rebooting/changing the driver of the LPC-Link module is giving you any problems it is most likely you have a problem with the power connections in your system. If your target is powered through the LPC-Link module it is most likely that you are drawing too much current on the 3.3V connection from the board.

Regards,

Rob

[lpcware]

Content originally posted in LPCWare by CodeRedSupport on Wed Jul 13 03:19:14 MST 2011

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Quote: navman


After much reading the posts, it seems most of these problems occur because the LPCxpresso IDE tries to reboot & change the driver for the LPC link. If Codered can build the LPC link firmware so this changing of drivers is not necessary (or atleast user can change depending on the need), then things will be much faster & less problematic. Is this possible Codered?

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No, this is not possible. LPC-Link contains an LPC3154 device, which is a RAM-only part. When powered on, the device enters DFU mode to allow the firmware to be bootloaded. The on-chip ROM has no other functionality, and you cannot use a DFU device as a debug probe...

When the firmware is loaded, the LPC3154 then 'becomes' an LPC-Link, but Windows then needs to load a different driver.

[lpcware]

Content originally posted in LPCWare by navman on Wed Jul 13 02:53:43 MST 2011
Thanks for the responses. It seem we have been able to trace the problems to an unshielded USB cable being used to power the board. Once we replaced it with a shielded USB cables, things are much better. Although, we still have sporadic problems where we have to unplug and replug the USB cable or even restart the PC sometimes to get the LPC link recognized.

After much reading the posts, it seems most of these problems occur because the LPCxpresso IDE tries to reboot & change the driver for the LPC link. If Codered can build the LPC link firmware so this changing of drivers is not necessary (or atleast user can change depending on the need), then things will be much faster & less problematic. Is this possible Codered?

[lpcware]

Content originally posted in LPCWare by Polux rsv on Tue Jul 12 00:00:54 MST 2011
When my CANUSB dongle is connected, the debugger ask me which device it should connect to. Try removing all USB devices, except keyboard and mouse obviously.

Angelo

[lpcware]

Content originally posted in LPCWare by ISTVAN on Mon Jul 11 17:48:02 MST 2011
[FONT=Calibri]We had a similar problem a year ago developing firmware for a different micro. It turned out all of our PCs used for development had worn out USB connectors. It took us a week to figure it out. I finally cut a USB cable open and hooked up a scope. Either D+ or D- was disappearing and Device Manager was dropping the connection immediately. These USB connectors a rated for 1000 insertions – I doubt we used it more than 200. [/FONT]
[FONT=Calibri]I hope this helps - Istvan[/FONT]

[lpcware]

Content originally posted in LPCWare by Rob65 on Mon Jul 11 12:34:06 MST 2011
Strange errors,

I have a similar environment (Vista 32 bits, SP2) and use LPCXpresso 4.0.5 but I have also used 3.2/3.4 and 3.6 on the same machine without any problems.

I also used this on XP and Windows 7 on different computers without any problems.
Sometimes I do get the "no emulator board available"  resetting the target (even in ISP mode) does not help - I have to unplug/replug the LPC-Link module to get this solved but this mostly only happens after my laptop has gone into sleep mode.

Have you also tried to run the tools on a different PC ?
I mean a different brand/type of PC. I have seen strange errors with certain PCs.
I have a Packard Bell PC that I am unable to use with a certain USB device. A clean Windows 7 Ultimate installed on that PC does not work with the device while another PC with the exact same Windows 7 version works withou any problems...
Although this was not a LPCXpresso board ther apparently can be problems with certain combination of PC and USB devices.

So my suggestion would be to try a different (brand of) PC.

Rob

[lpcware]

Content originally posted in LPCWare by CodeRedSupport on Mon Jul 11 12:14:23 MST 2011
[FONT=Arial][SIZE=2]Sorry to hear you're having trouble. [/SIZE][/FONT][FONT=Arial][SIZE=2]First, refer to the[/SIZE][/FONT][FONT=Arial][SIZE=2] "[/SIZE][/FONT][FONT=Arial][SIZE=2][B]Debug target connections[/B]"[/SIZE][/FONT][FONT=Arial][SIZE=2] information on the Code Red Support Wiki:[/SIZE][/FONT][FONT=Arial][SIZE=2]

http://support.code-red-tech.com/CodeRedWiki/CodeRedFAQ[/SIZE][/FONT][FONT=Arial][SIZE=2]

We'll need to know the version of LPCXpresso you have installed, and relevant details about your Windows/Linux operating environment to assist further.[/SIZE][/FONT][FONT=Arial][SIZE=2]

Regards,[/SIZE][/FONT][FONT=Arial][SIZE=2]
CodeRedSupport[/SIZE][/FONT]