yoho Posted October 21, 2009 Report Share Posted October 21, 2009 Hi all, I have a core and some on a veroboard. It is working ok. With a 16x2 LCD with backlight. If I replace this with a 40x2 (without connecting the backlight) the core gets confused. It keeps restarting and sometimes shows the application but mostly can't get past the MIOS intro. After a couple of restart it stops al together. Changing back to the 16x2 solves the problem. Power is at a steady 5V and the core keeps shouting through MIDI out for a download... Can somebody give a pointer how to solve this? Could the length of the wire (15 cm= 6 inch) be the problem? I've checked the diagram and only thing so far missing are the two 100n condensors on the powerlines near the PIC. I know those are there for a reason, but I didn't install them because all my stock was consumed by another project. Cheers, Erik Quote Link to comment Share on other sites More sharing options...
lylehaze Posted October 22, 2009 Report Share Posted October 22, 2009 Hi all, I have a core and some on a veroboard. It is working ok. With a 16x2 LCD with backlight. If I replace this with a 40x2 (without connecting the backlight) the core gets confused. It keeps restarting and sometimes shows the application but mostly can't get past the MIOS intro. After a couple of restart it stops al together. Changing back to the 16x2 solves the problem. Power is at a steady 5V and the core keeps shouting through MIDI out for a download... Can somebody give a pointer how to solve this? Could the length of the wire (15 cm= 6 inch) be the problem? I've checked the diagram and only thing so far missing are the two 100n condensors on the powerlines near the PIC. I know those are there for a reason, but I didn't install them because all my stock was consumed by another project. Cheers, Erik Your problem is almost certainly power. The bigger display draws more than the smaller one, and the missing caps at the PIC only make the problem worse. Get the caps in close to the pic, and add an extra one where the display power leaves the board. If that doesn't solve it, try a bigger power supply. You could even TEST this idea by using +5 volts from a computer hard drive connector as a test power supply. (NOT a USB port, those may be current limited) Good Luck, LyleHaze Quote Link to comment Share on other sites More sharing options...
yoho Posted October 22, 2009 Author Report Share Posted October 22, 2009 With a :blush: i have to admit that it was a stupid thing forgetting the capacitor. I installed a cap under the pic (which is close to the lcd connector) and that worked! Thanks for the help! (note to self: don't save money on caps...) Quote Link to comment Share on other sites More sharing options...
nILS Posted October 22, 2009 Report Share Posted October 22, 2009 SmashTV said that to me a while back (some years ago): "See how leaving out a 10 cent part has got you chasing your tail?" :thumbsup: Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.