fcebreros Posted November 7, 2011 Report Share Posted November 7, 2011 (edited) Any idea what is happening? I thought it was the lcd but every time I power it on the mistakes change. Its an LPC Core powerede trough USB from a 2A hub, only SD Card connected. I'm using a 74hc595 on the ldc's. Best Frank Edited November 7, 2011 by fcebreros Quote Link to comment Share on other sites More sharing options...
sparx Posted November 8, 2011 Report Share Posted November 8, 2011 Try a different or shorter cable. Check all connections 3 times if you soldered it. Regards S Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted November 8, 2011 Report Share Posted November 8, 2011 (edited) +1 if things are fluctiating/different all the times, it could well be the cables or solder connection points. As both displays are affected, cable length can be the problem, as sparx said... or a bad solder point on the core itself... so pls recheck the core, also... :) for for additional testing, you can always exchange with a completely different display type from another manufacturer (if you got one) or an other core (if you got one). Greets, Peter Edited November 8, 2011 by Hawkeye Quote Link to comment Share on other sites More sharing options...
Antix Posted November 8, 2011 Report Share Posted November 8, 2011 Hi, May I am wrong but it seems to me that a single USB port can power 500mA at least, no matter if the hub is 2 Amp. I think it may be a current consumption problem. Why dont you try with an external power? Regards Antix Quote Link to comment Share on other sites More sharing options...
sparx Posted November 8, 2011 Report Share Posted November 8, 2011 Thats a good point too and certainly worth trying, but core, SD card and LCD shouldn't pull more than 500mA? Mine is configured with much more and powered by single USB. That said, as part of an ebay haul, I got another USB cable and that didn't work very well (in the bin, no messing about!), so maybe try another USB cable first? Or try connecting directly to the USB port without the hub? S Quote Link to comment Share on other sites More sharing options...
fcebreros Posted November 9, 2011 Author Report Share Posted November 9, 2011 I' have shorten the cable and tried different powersources and nothing. I have also checked the board with a magnifying glass and resoldered any suspicious joint, and still the same problem. With the stm core the displays worked. I have read something about the data speed messing up things. Does the lpc core send the data to de lcd's at a higher speed? Thanks Frank Quote Link to comment Share on other sites More sharing options...
sparx Posted November 9, 2011 Report Share Posted November 9, 2011 Can you check the LCD and cable work on another core? Another thing you could try is to reflash the LPC and see if that cures the problem. Quote Link to comment Share on other sites More sharing options...
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