questionable Posted August 13, 2009 Report Share Posted August 13, 2009 Howdy Midiboxers. I've finally finished the wiring on my box, but am having some difficulty as the LCD shows only a row of black boxes on the top row, and never displays the ready text. The midi firmware upload seems to have worked fine (no errors), so I expect that MIOS is loaded properly. I'd like to make sure that my pin assignments are correct on my LCD, but I don't have any way of telling what brand/model number my LCD is. Does anyone recognize this display?I remember there was a sticker on the display that had some numbers, but that has been removed. I believe I may have purchased the display from SmashTV, but that was several years ago. Any help is much appreciated. Quote Link to comment Share on other sites More sharing options...
Janis1279 Posted August 13, 2009 Report Share Posted August 13, 2009 Hi.Mios suports your's Epson SED1278 chip LCD display.You need compare are you soldering wires as in :http://www.ucapps.de/mbhp/mbhp_lcd.pdfIn your case LCD pins are grouped in the odd and even columns, but pin meanings are the same as in a one row, I think.Regards , Janis Quote Link to comment Share on other sites More sharing options...
questionable Posted August 13, 2009 Author Report Share Posted August 13, 2009 Yep, I've triple checked the connections per that diagram. Right now the backlight isn't working, but I think I recall on the datasheet I had at one point (can no longer find) that the +/- were flipped on this display, so swapping those should fix the backlight. I was hoping to find the datasheet again, so that I could double check that the pin assignments on the LCD were the same, but without the serial number of the LCD, I have no hope of finding that data sheet.If the LCD is working in general (although just displaying black boxes along the top, contrast controls do work), I suppose maybe I should be looking elsewhere for the problems. What's odd is that after uploading MIOS, the midibox is acting correctly (ie, only sends one upload request after powering up, instead of the continuous stream it was doing before), so my thoughts are that MIOS is operating correctly...which leads me back to thinking that the LCD is not working correctly. Perhaps my next step should be this (from the wiki)How can I test if MIOS is running?After the startup phase, you can send this message “F0 00 00 7E 40 00 0F F7†to the core, MIOS should reply with the same message immediately. You could also try to upload an application, after every code block a checksum message will be send which acknowledges that the stream has been received correctly. Quote Link to comment Share on other sites More sharing options...
ssp Posted August 13, 2009 Report Share Posted August 13, 2009 mmm reminds me of a little thing i did which was "not enough power to the core" it was only after nils checked this with me that i found the right supply and pumped a min of 9v into the core that everything lit up as it should. you got enough power going into the core?also check for shorts, missed solder pins etc, and if you have a ribbon block on the end of the cable it is possible that in clamping it down its shorted it there. Quote Link to comment Share on other sites More sharing options...
questionable Posted August 13, 2009 Author Report Share Posted August 13, 2009 Good ideas, all of them. I suppose the issue is that there's really so many interesting and fun ways that I could have botched this thing...it's hard to wrap my head around where to start. :) Quote Link to comment Share on other sites More sharing options...
questionable Posted August 13, 2009 Author Report Share Posted August 13, 2009 The plot thickens. While trying to figure out how to send that string to MIOS to see if it returns correctly, I decided to try reuploading the update_without_installed_mios hex file, which then didn't work, gave me some errors. I then decided to try an upload from an older version of MIOS, which also didn't work, but the LCD gave me an error message saying "no update". So I guess the LCD is working, and it's an issue with MIOS not installing correctly or completely. Quote Link to comment Share on other sites More sharing options...
questionable Posted August 13, 2009 Author Report Share Posted August 13, 2009 Alright, so I've managed to get MIOS installed (i think), but the LCD is only reading "Bootloader is Up to Date", I never get the Ready text. From what I'm reading, this is not correct. Should I continue loading the application at this point? Quote Link to comment Share on other sites More sharing options...
clem! Posted August 13, 2009 Report Share Posted August 13, 2009 hi questionable,if you didn`t see any text only blocks and the upload request is send - it could eventually help to change the contrast of the lcd.Best reegards clem! Quote Link to comment Share on other sites More sharing options...
questionable Posted August 14, 2009 Author Report Share Posted August 14, 2009 It was not the LCD after all, just failed attempts at uploading MIOS. I ended up trying a manual upload with a longer delay between sends. All is well...sort of, but I'll post another topic, as it's completely unrelated. Quote Link to comment Share on other sites More sharing options...
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