Snyderman Posted October 21, 2011 Report Share Posted October 21, 2011 (edited) Hey everybody, I've been putting together my sammichSID after putting it off for ...about a year and a half, but it's been going really well (started about a month ago working on weekends when I have time). I've done all of my voltage checks, I've uploaded the Sammich_SID.hex file with no errors but I have a problem with the LCD. When I turn the trimpots down to the left, I get the rectangles, but I can't seem to find any combination that will show me any text. It should be there, since it's been uploaded and the lights blink when the Sammich powers on. To start I had a few slight mishaps earlier that may affect it. I have one of the holes in that's unrelated to all of the pins with a blob of solder on it, but it's not bridged to anything. Also when I set it up originally I had the shunt position for a 25mA LCD (I guessed wrong, it needed to be in the 250mA position). Did I fry my LCD or am I missing something obvious? I really don't know what I need to do to test it right now, so any advice is welcome. Edited October 21, 2011 by Snyderman Quote Link to comment Share on other sites More sharing options...
Wilba Posted October 21, 2011 Report Share Posted October 21, 2011 If any of the pins on the LCD header have shorts or are poor solder joints, then the LCD may not get the correct initialization data and so nothing will display. So you should check continuity between pins on the bottom of the PCB with pins on the LCD header... and then also check that there are no pins shorting. You should ALSO test where those pins connect to the PIC... a bad solder joint there (or short) will cause the same problem. Refer to the PCB layout PDF in the wiki: http://www.midibox.org/dokuwiki/sammichSID to find out which PIC pins connect - they start at pin 1 and go down the "right" side of the PIC. Since I test all the LCDs and you apparently can see the rectangles, it's a good sign that the LCD isn't dead, just not receiving the right data. Quote Link to comment Share on other sites More sharing options...
Snyderman Posted October 21, 2011 Author Report Share Posted October 21, 2011 (edited) I went back and corrected some leads that weren't stable and all's well. Thanks Wilba. Also this project is super awesome. Also, I accidentally melted one of the corners of one of the button caps by mistake, haha. What was the part number so I could order another one, or could I send you some money and have you ship me a few extras? Just the rectangular plastic caps, not the round buttons that are soldered to the board. EDIT: Well now I have a new problem, or a head scratcher anyway. I'm looking through the MBSID V2 manual trying to go into sub menus, but I can't get beyond the starting screen with any regularity. Buttons and the encoder seem to work randomly. Perhaps the buttons themselves aren't soldered properly? I've seen menus change here and there but I can't reproduce any particular things. They're pushed all the way in, so I'm not sure why they're not responding. My one thought would be that I soldered all of the pins on the bottom but not on the top and because of that they're not making solid enough connections? Unless I misread the instructions I thought I only needed to solder from the bottom since all of the other components seem to be working fine (though maybe buttons are different?). Also, the bansksticks and SIDs aren't installed yet. Edited October 21, 2011 by Snyderman Quote Link to comment Share on other sites More sharing options...
Wilba Posted October 22, 2011 Report Share Posted October 22, 2011 I can send you spare button caps. How about we wait until everything is working, I might need to send you some other parts. If ALL your switches and encoder aren't working, then it could be some problem with the shift registers. Check the resistor networks are soldered the right way, with the dot on the resistor network matching the dot on the PCB. If correct, you should only see the dots on two of them, the other two will be on the side next to the IC and hidden. I suspect the problem might be with the headers, though... since you just had a similar problem with the LCD. A bad connection there and you won't get correct data in or out. But essentially you'll need to check joints everywhere... on the ICs, the resistor networks, the switches and the headers, and then even on the PIC where the header pins connect. You don't need to solder the switches from the top, the holes are plated, so it's connected to the tracks on the top layer. Try the CS test app, found on the wiki page under "sammichSID Troubleshooting" That should give you an idea if the problem is specific to some switches or all of them. Quote Link to comment Share on other sites More sharing options...
Snyderman Posted October 22, 2011 Author Report Share Posted October 22, 2011 (edited) I haven't had a chance to check the soldering yet (since this morning when I fixed the LCD), but I uploaded the CS App, the LEDs seem to work perfectly but the buttons all have issues. Menu buttons 1 and 2 (top left two of the five) work if jiggled around vigorously (but not pressed) and the rotary encoder seems to work from time to time. I'll check my connections. Could you clarify what you mean by checking the dots on the resistor networks? I'm like 99% sure I double and triple checked before putting in any resistors and made sure any diodes were oriented the right way. EDIT: Okay, so I've rechecked my soldering and it seems to have a slight effect. I saw it flickering between pressed and released, and more of the buttons seem to be responding. It probably is my soldering on the header pins or at least the ones on the actual LCD. I'm still not getting it though :( It does seem to be universal to the buttons, and the encoder, but they're overall slightly more responsive. Some buttons that didn't work before work now (if you jiggle them) and buttons 1 and 2 (the most responsive) stay in that flicker pressed/unpressed state if you hold the button at an angle, where before it took significant jiggling to get anything out of them. On further examination, the only buttons that make any kind of response so far are the top five. The bottom three and the four shift/menu/up/down don't seem to respond hardly at all. EDIT2: I think I'm mentally challenged. I think I figured out what you meant by the dots on the board... for resistors which are CURRENTLY UNOCCUPIED!!! Goddamn it. I'll be back in a second. EDIT3: Okay. The resistors being in helped! The Banksticks are formatted beautifully. Now I'm going to upload some of the patches and then finally install the SIDs. Edited October 22, 2011 by Snyderman Quote Link to comment Share on other sites More sharing options...
Snyderman Posted October 22, 2011 Author Report Share Posted October 22, 2011 (edited) Okay, last dumb question. I got all of my stuff working, I put in the banksticks, they formatted, I got the patches via sysex, I put the SIDs in and the voltage is a tiny bit low (8.71 with both SIDs, it's a weak PSU) and I read the instructions but I'm not sure how to install the capacitors. Do I just clip the leads and sit them in there or do they need to be soldered in place? The strips themselves have been soldered to the board since the base PCB steps. Just want to be extra clear. Also I've got the 6582s, in case it wasn't clear. I know I need the 22nF capacitors. Edited October 22, 2011 by Snyderman Quote Link to comment Share on other sites More sharing options...
Snyderman Posted October 24, 2011 Author Report Share Posted October 24, 2011 After watching the Youtube time lapse video, I see it was just stuffing them in place. The beast works, and it sounds friggin great. I can't believe I don't have any TRS cables, so I'll need to get some tomorrow. Quote Link to comment Share on other sites More sharing options...
Wilba Posted October 25, 2011 Report Share Posted October 25, 2011 LOL those switches were then connected to digital inputs that were then not connected to either a high (5V) or low (0V), just floating and being whatever they liked. They were then connected to 0V when the switch was pressed, but when not pressed, random garbage. Don't solder the 22nF caps. Those sockets are so you can swap the caps to match the SID type, or use different caps, not that you are likely to do that. Quote Link to comment Share on other sites More sharing options...
bruler Posted October 25, 2011 Report Share Posted October 25, 2011 Can I just clarify something here. I amn't getting a backlight and thought it was because I am only getting 11v into the bridge rectifier. I am replacing it to see if that might be the issue (12v comes in so it isn't PSU, but drops to 11v at rectifier). My question: should the pins in JBL be in 5v AND 12v for the LCD supply (default high-power one)? The more I think about it the more it seems like the answer is NO! (stupid=P) This is the only issue I have but as I amn't getting 12v I only see blocks on LCD (have tested and resoldered all pins of LCD too). Any help gratefully received=) Quote Link to comment Share on other sites More sharing options...
Wilba Posted October 26, 2011 Report Share Posted October 26, 2011 The outer pins on JBL are 5V and 12V respectively. Putting a shunt in the left or right position will connect either 5V or 12V to the middle pin, which is connected to the backlight. It may not be exactly 12V on the 12V pin, as it is actually the input voltage, after passing through the bridge rectifier, so for unregulated PSUs it will vary with load. Blocks on the LCD have nothing to do with the backlight working or not. They indicate the LCD is being powered by 5V (on a different pin) but not receiving the right data to initialize and display characters. You will need to check the connections on the headers and the LCD and PIC pins to which they connect. Quote Link to comment Share on other sites More sharing options...
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