d2k Posted February 2, 2003 Report Share Posted February 2, 2003 So after 100+ posts I finally have my 1st mbhp box made - a lil MBSID before i start on the bigger pies (2xMB64 and a LC)...Voltages all good throughout, and LCD (backlight aint workin tho - do i need to connect the A and K pins on it to nefin?) reads correct - boots with SID v1.4 then goes to:P: 1 C: 1 D:1Internal PatchHowever, i cant yet hear the beast in action :( as i dunno how to connect the audio out to a 3 -pole jack socket i have, i've tried various ways but have had no luck... am i right in thiniking 2 of the poles have to be bridged? which ones?Also, can i just connect up the MIDI in/out from the core and tinker about straight away - i.e i dont have to load any sysex files etc...?What do i do? I must hear this thing sooon ;DPeace...Dan Quote Link to comment Share on other sites More sharing options...
d2k Posted February 2, 2003 Author Report Share Posted February 2, 2003 ;D ;D ;DBurnt the test firmware...and BINGO - T's loverly choard played upon me!! ;)LCD read 'Last Received' afterwards - is that normal?Nows all i need to sort out is the LCD backlight... Quote Link to comment Share on other sites More sharing options...
d2k Posted February 3, 2003 Author Report Share Posted February 3, 2003 ;D ;D ;D ;D ;D ;D ;D ;D ;D ;Dsorry, i had to smile again - this thing is a beast!!! ;)Thorsten! what have u created....???!!!U got me hooked, line and sinker with this for while now - mucho rpsx for it all...Dan Quote Link to comment Share on other sites More sharing options...
TK. Posted February 3, 2003 Report Share Posted February 3, 2003 You're welcome! :DGood that I've also created a test firmware... because without MIDI input the SID will play no sound ;-)Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
LO Posted February 3, 2003 Report Share Posted February 3, 2003 HiCheck that your wires running to the backlight pins are round the right way because the backlighting is normally by LED so the current will only flow one way.The A & K pins are normally connected to the respective pins from the main connector via conductive tracks on the LCD board; Check them with a meter to confirm this, if they are you do not need to hook them up. You should have a data sheet with your LCD to confirm this?'ight?LO Quote Link to comment Share on other sites More sharing options...
d2k Posted February 3, 2003 Author Report Share Posted February 3, 2003 yeah, lcd2core connection looks okay (displaytech 162). a & k pins have some current going through them...so i guess summin else is a miss...i am measuring 5v on pins 15/16 ( led + & -) of the lcd, so it should work right? mebbe it's just gone? i dunno, i did mess about with the lcd prior to putting it into this box...o well, i whiped in an ltc module with sum ultrbright blue leds that make up for it neway ;), still a mystery tho ???cheers fellaz...D Quote Link to comment Share on other sites More sharing options...
d2k Posted February 3, 2003 Author Report Share Posted February 3, 2003 bingo ;)connected pin A on the LCD to pin 15 (+5), and there she lit! should K be left open or conneced to 16?nanice...D Quote Link to comment Share on other sites More sharing options...
TK. Posted February 4, 2003 Report Share Posted February 4, 2003 If it lits now, just let it open. Normaly this connection isn't necessary, pin 15 is A and pin 16 is K... :-/Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
d2k Posted February 6, 2003 Author Report Share Posted February 6, 2003 :-[ uh-oh...So, eveything was runnin smooth, but then after i housed it it in it's new home and turned it out I got nothing but a blank screen...:(I dismantled it all again, and checked voltages - on the core i'm not gettin the +5 between IC1(1)-(12) nemore, but all other voltage test are okay...Does anyone know what has happened here...?taDan Quote Link to comment Share on other sites More sharing options...
d2k Posted February 6, 2003 Author Report Share Posted February 6, 2003 After testing the sid module for voltages, theres probs there too :| IC1 is fine, IC2 and 3 are also not gettin the +5...Damn, i guess summin was bound to go wrong :( having it work first time was too good to be true..;)elp Quote Link to comment Share on other sites More sharing options...
d2k Posted February 7, 2003 Author Report Share Posted February 7, 2003 ???Okay, voltages are all good again...Still getting a blank screen when i power up (think thats because i may of killed the LCD even tho the backlight lights up). Tried testing with the SID test f/w, and didnt get the choard sound like before...Checked for track breaks and shorts - all looked okay, even tried swapping the SID, also burnt a new PIC - still no worky tho :(...Any ideas pls....?I'm gonna make some new modules, but i'm feelin pretty gutted round about now ... :-/ Quote Link to comment Share on other sites More sharing options...
d2k Posted February 8, 2003 Author Report Share Posted February 8, 2003 right, stuffed 2 new sid and core modules with new components, checked voltages - all good, burnt sid test f/w and powered up - choard sound played, great ;). But then after powering down and turning back on - silent once again :(what is happening here?I'm using a 15v wallplug for both modules Quote Link to comment Share on other sites More sharing options...
TK. Posted February 8, 2003 Report Share Posted February 8, 2003 Hi Dan,the failures are very strange, it seems that there is a very dangerous "bug" in your circuit. I hope that you"ve isolated the crystal at the bottom side with a sticky tape? Is there any physical connection between the voltage domain before and after the 7805? Are the jumpers connected properly?Maybe you should also test some other firmwares in order to ensure that the PIC is still working. Are you still using the "mirrored" PCB?Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
Ian_Hurlock Posted February 8, 2003 Report Share Posted February 8, 2003 If it makes you feel better, I had the same problems with my core + SID. I ended up with only a bunch of black lines on my LCD and nil from my SID.I have no suggestions beside that I had the fault once and changed the audio transistor on the SID.Then it worked for a bit. Then it stopped again.Actually it seemed to go pearshaped after I added the lcd ???Not that that makes real sense ???Still the lcd was wrong even when I stuffed new parts also.In the end I gave it up for a bad joke :'( :-/ ???One day I will try againIan Quote Link to comment Share on other sites More sharing options...
LO Posted February 8, 2003 Report Share Posted February 8, 2003 Make sure you have a fuse inline with your P/S to save any damage when you get a short I went through about 8x 400mA fuses when I was testing!BTW my LCD works fine :P (sorry) Quote Link to comment Share on other sites More sharing options...
TK. Posted February 8, 2003 Report Share Posted February 8, 2003 It\s time to find the root cause!Ian: is your PIC still functional? Does it work with other firmwares? Ian/Dan: is your SID clocked with an additional 1 MHz oscillator or with the PIC?Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
Ian_Hurlock Posted February 8, 2003 Report Share Posted February 8, 2003 I had more success with the earlier firmware.I tried my lcd with LO's mf core and it would not work there either. So I think i may have fried the LCD driver.I am using the 1mhz from the core pic.I have stuffed different SIDS into the thing with the same resultIt seems like something gives out after a while.The first time it happened I replaced the Transistor on the core and the SID and it worked for a while then nothing.I have reused the PIC on other projects with no trouble.I am not using the 8580 And I do not have the same problems with voltage as Dan.It seems as if something gets tripped then nothing.I have replaced all the parts including the pic.Don't be too worried though, I am waiting to build the thing fully as a synth + control surface with the 18F.Thanks Ian ;) Quote Link to comment Share on other sites More sharing options...
d2k Posted February 8, 2003 Author Report Share Posted February 8, 2003 I hope that you"ve isolated the crystal at the bottom side with a sticky tape?Not with tape, but it's def not touching any other tracks...Is there any physical connection between the voltage domain before and after the 7805? I'm goin from the dc jack to a switch, then to a fuse (1.0A), then to a LED/1k resitor (power LED) as described in the MB64 walkthrough...before feediing both the SID and Core modules...voltages all good on both circuits...Maybe you should also test some other firmwares in order to ensure that the PIC is still working.Yeah, ok i'll do that - but it seems like the same prob Ian was having - I tried using the same pic/sid from the first ones in the new modules, and it worked first time (sid test f/w), then nothing - like in the 1st box, so it seems somthing on the circuit is blowing - mebbe the transistor like u said Ian...Are you still using the "mirrored" PCB?Nope, these where on brand new brds i etched n stuffed...Ian/Dan: is your SID clocked with an additional 1 MHz oscillator or with the PIC?1mhz osc...I do not have the same problems with voltage as DanThats the thing, voltages are good now...so it seems we have a same or similar prob...then again, this is electronics - what do i know :P :-X :-/ :'( :-*oh well, onwards n upwards...Thanks guys...Dan Quote Link to comment Share on other sites More sharing options...
TK. Posted February 8, 2003 Report Share Posted February 8, 2003 There is possibly a way to freeze the LCD driver, and thats a floating signal at pin RB7 of the PIC.Dan: could you please temporary remove the LCD and solder a 1k or 10k resistor from Pin #40 of the PIC to ground?If this doesn't help, I will provide a very reduced test program for the SID which *must* work.Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
TK. Posted February 8, 2003 Report Share Posted February 8, 2003 Another check to determine if the SID can be accessed by the PIC: at power-on, the reset signal of the SID (Pin #5 of the SID chip) is going low for about three seconds, thereafter it goes to +5V. This can be measuredBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
d2k Posted February 8, 2003 Author Report Share Posted February 8, 2003 tried 1k and 10k resistor, still nothing... unless u meant this is a check for the LCD and not the SID (i dont have the lcd connected on this core...Another check to determine if the SID can be accessed by the PIC: at power-on, the reset signal of the SID (Pin #5 of the SID chip) is going low for about three seconds, thereafter it goes to +5V. This can be measured So, test pin 5 against what other pin, ne pin goin to ground right? ie pin 14...? I tried, no +5 there either - 0.934 is what it seems to reach... Quote Link to comment Share on other sites More sharing options...
TK. Posted February 8, 2003 Report Share Posted February 8, 2003 Ok, so the 74HC595 shift registers are not serviced by the PIC. Now it's important to know if the firmware is running before debugging the SID module. Here some voltages, which have to be measured against ground:Pin #1: > 4VPin #17: ca. 2 V (must be > 1V and < 4V)Pin #19: < 1VPin #20: > 4VPin #21: < 1VPin #22: > 4VBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
d2k Posted February 8, 2003 Author Report Share Posted February 8, 2003 This is on the core runnin the SID test module...Pin #1: > 4V yepPin #17: ca. 2 V (must be > 1V and < 4V) yepPin #19: < 1V yepPin #20: > 4VyepPin #21: < 1VyepPin #22: > 4Vnope, gettin 0V...Does this narrow it down?Thanks TDan Quote Link to comment Share on other sites More sharing options...
d2k Posted February 8, 2003 Author Report Share Posted February 8, 2003 i meant runnin the SID test f/w...;) Quote Link to comment Share on other sites More sharing options...
TK. Posted February 8, 2003 Report Share Posted February 8, 2003 Ok, your PIC is still working - perfect. With the test firmware, the voltage level of Pin #22 can be ignored.Now check the interconnections between Core and SID module (again)Thereafter measure the voltages on the 74HC595 chips:Pin #10 and #16 of IC2 and IC3: >4VPin #2 of IC2: >4VBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
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