zgba Posted April 15, 2009 Report Share Posted April 15, 2009 I recently built an OPL3 module. It's connected to CORE running PIC18F4685. After reading some posts I changed the MIOS to '462 version and managed to run the interconnection test, but nothing more. I can't force the FM module to make a sound. When I power up only the core module, the LED on OPL3 lights up (is that normal?). Then I change the modwheel values and I have readouts on corresponding pins, *but* when I switch to pin J2_1:WR, the LED lights brighter, and I have only about 4,95V (my PSU gives about 5,1V). On pins from J2_1:D0 to J2_2:D7 - LED gets brighter and only 4,5V. I tried another PSU (and I know it's a good one, 'cause it works with my mbSID), but no change. I have a bad feeling, that my YMF262 is damaged and I have no spares. Any suggestions? Quote Link to comment Share on other sites More sharing options...
Wilba Posted April 16, 2009 Report Share Posted April 16, 2009 I think the PIC18F4685 shouldn't be used, because it reserves two pins from port B for CAN bus, so that may prevent correct data signals getting to the YMF262. It is best to use a PIC18F452 but I have make mine work with PIC18F4620 also.Only install the MIOS 1.9f .hex file that matches the PIC type.Check you are supplying 5V/Ground to the OPL3 module via header J1. I know that if there is no 5V supplied, the LED will still be on during interconnection tests, as the YMF262 will be powered from the data lines!If you are not connecting ground at J1, you need to connect the ground of the Core module to the ground of OPL3 module and the ground of the +12V/gnd/-12V supply (J3).The voltages you measure during interconnection test will not all be 5V, as some pins get used for other things like LCD control, so they will not be at 5V all the time, and your meter will average it.ALSO cable length between Core and OPL3 modules should be short, as mine didn't work at 35cm, it should be < 15cm.Do these checks and report new results... it's quite possible your YMF262 is good. Quote Link to comment Share on other sites More sharing options...
Imp Posted April 16, 2009 Report Share Posted April 16, 2009 I had nearly the same issue, when i built the FM with a PIC18F4685.I got it to work by flashing the MIOS for PIC18F452 but this might lead to different problems.Wilba, can you explain what might go wrong? Quote Link to comment Share on other sites More sharing options...
zgba Posted April 16, 2009 Author Report Share Posted April 16, 2009 Thanks for quick reply! First I trimmed off the cables connecting OPL3 and CORE; now they're <10cm long.TEST RESULTS:#1 PIC18F4685 with mios_v1_9f_pic18f4685.hexCORE connected to +5VOPL3 connected to +5Vcommon groundinterconnectrion test: # 0: Pin J2_1:RS = 5,12V; Pin J2_1:D0 = 4,94V; Pin J2_1:D1 = ~0,9V; Pins J2_2:D2, D3 = 4,94V # 1: Pin J2_1:A0 = 5,12V; Pins J2_1:D0, D1, D2, D3 = 4,94V # 2: Pin J2_1:A1 = 5,12V; -//- # 3: Pin J2_1:WR = 5,12V; -//- # 4: Pin J2_1:D0 = 4,94V; Pins J2_1:D1, D2, D3 = 4,94V # 5: Pin J2_1:D1 = 4,94V; Pins J2_1:D0, D2, D3 = 4,94V # 6: Pin J2_2:D2 = 4,94V; Pins J2_1:D0, D1, D3 = 4,94V # 7: Pin J2_2:D3 = 4,94V; Pins J2_1:D0, D1, D2 = 4,94V # 8: Pin J2_2:D4 = 5,12V; Pins J2_1:D0, D1, D2, D3 = 4,94V # 9: Pin J2_2:D5 = 5,12V; -//- #10: Pin J2_2:D6 = 5,12V; -//- #11: Pin J2_2:D7 = 5,12V; -//-#2 PIC18F4685 with mios_v1_9f_pic18f452.hexCORE connected to +5VOPL3 connected to +5Vcommon groundinterconnectrion test: # 0: Pin J2_1:RS = 5,12V # 1: Pin J2_1:A0 = 5,12V # 2: Pin J2_1:A1 = 5,12V # 3: Pin J2_1:WR = 5,12V # 4: Pin J2_1:D0 = 5,12V # 5: Pin J2_1:D1 = 5,12V # 6: Pin J2_2:D2 = 5,12V # 7: Pin J2_2:D3 = 5,12V # 8: Pin J2_2:D4 = 5,12V # 9: Pin J2_2:D5 = 5,12V #10: Pin J2_2:D6 = 5,12V #11: Pin J2_2:D7 = 5,12V#3 PIC18F4685 with mios_v1_9f_pic18f452.hexCORE connected to +5VOPL3 connected to +5V and +/-5Vcommon groundgood voltages @ opamp sockets then opamps stuffedtesttone gives no sound#4 PIC18F4685 with mios_v1_9f_pic18f4685.hexCORE connected to +5VOPL3 connected to +5V and +/-5Vcommon groundgood voltages @ opamp sockets then opamps stuffedtesttone gives no soundAnything that I can hear is some digital noise when transmitting MIDI data. Conclusion - CORE works, opamps work, or I am wrong? Is it an easy way (I don't have a scope) to see if the digital transmission between YMF and DAC works? Everything I know about these 2 chips is that they were working on the soundcard. Before desoldering of course:) Quote Link to comment Share on other sites More sharing options...
zgba Posted April 16, 2009 Author Report Share Posted April 16, 2009 And there are some photos of my setup. I'm using an old PC PSU, that gives +/-5V and +10V/-11V instead od 12, so I don't use it. As you can see I have a brand new GM5 that I'm really proud of. And I know, I have the ugliest 100nF caps in the whole Midibox Community;) Quote Link to comment Share on other sites More sharing options...
nILS Posted April 16, 2009 Report Share Posted April 16, 2009 Those are some neat high-voltage caps you're using there ;) And I hereby retract my Wilba-Drunken-Monkey-Soldering comment...Did you really really check _everything_ for bridges / broken tracks / ... ? Quote Link to comment Share on other sites More sharing options...
Imp Posted April 16, 2009 Report Share Posted April 16, 2009 OPL3 connected to +5V and +/-5Vit should be +/-12 V or is it a typo? Quote Link to comment Share on other sites More sharing options...
zgba Posted April 16, 2009 Author Report Share Posted April 16, 2009 @nILS - checking for bridges/cold joints is what I do everyday before I go to sleep:) I do continuity tests and resistance checks. This mess is caused by desoldering wrong placed YAC and reheating joints.@Imp - It's not a typo. OpAmps can be powered from +/-5V to +/-18V and I have only +/-5V PSU atm. Quote Link to comment Share on other sites More sharing options...
nILS Posted April 16, 2009 Report Share Posted April 16, 2009 Warning - while you were typing a new reply has been posted. You may wish to review your post.Anyways: The opamps would run on +-5V as well, they might clip a lot and the sound maybe shite but it should work. Quote Link to comment Share on other sites More sharing options...
zgba Posted April 17, 2009 Author Report Share Posted April 17, 2009 When I get this synthie to work, I make a reasonable PSU - 5V @1A and +/-12V @2x500mA. Till then +/-5V must suffice. I just found a guy that might have a tasty soundcard for about 2 Euros. First I'll solder the second YAC and see if it helps. If not - continuity tests once more and maybe replacing YMF. Or maybe you guys have some better ideas? Cheers! Quote Link to comment Share on other sites More sharing options...
Imp Posted April 17, 2009 Report Share Posted April 17, 2009 Have you tried connecting the LCD in 8-bit-mode?Since the mios for the '452 expects 8bit, and the used pins also control the YMF, this can make a difference. Quote Link to comment Share on other sites More sharing options...
zgba Posted April 17, 2009 Author Report Share Posted April 17, 2009 Nope, I only connected the LCD in 4bit mode but it was when running '4585 firmware. I saw 'ready' message, interconnection and testtone messages, and some garbage after uploading mbFM software. After switching to '452 firmware I don't use the LCD. I know I should wire it in 8bit mode but I don't want to desolder the wires, cause it's a part of my *working* mbSID. When I find an appropriate 2x40 LCD, I'll connect it in 8bit mode. Quote Link to comment Share on other sites More sharing options...
zgba Posted April 22, 2009 Author Report Share Posted April 22, 2009 Yesterday I bought another soundcard. I'm waiting for the delivery now and than we'll see if that works. Quote Link to comment Share on other sites More sharing options...
zgba Posted April 28, 2009 Author Report Share Posted April 28, 2009 My soundcard arrived today, pretty, isn't it?:) Next step: to desolder everything useful, then back to debugging my OPL3 module. Quote Link to comment Share on other sites More sharing options...
Schrittmacher Posted April 28, 2009 Report Share Posted April 28, 2009 i dont now exactly what is your problem, but i think the voltage is to low. the stabilize circuit on the core module needs min. 7,0 volts for a proper funktion. you need min 2,0 Volt between 5 Volt circuit voltage and the voltage on your PSU! Quote Link to comment Share on other sites More sharing options...
zgba Posted April 28, 2009 Author Report Share Posted April 28, 2009 My core module runs from stabilised PSU. Bridge, 7805 and caps aren't mounted on my pcb, and it works. So it's ok. But in the meantime I installed second YAC512 and swapped YMF262 and nothing changed. I think the problem is in communication between core and OPL. I think my '4685 wants to be replaced with '452... Quote Link to comment Share on other sites More sharing options...
zgba Posted June 5, 2009 Author Report Share Posted June 5, 2009 I just bought PIC18F452. I'll program it, replace '4685 with it and check if it helps later. Wish me luck. Quote Link to comment Share on other sites More sharing options...
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