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From nothing to 2 working SIDs?? (mono6581 and MB6582)


jooks
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After some searching and reading I gather that the 2.74V on IC14 doesn´t indicate any trouble since it´s hard to get a reading due to the crystal. I also think the 3.99V from IC25 tx is not unusal and doesn´t indicate any problem. Or? My first reading at IC25 was about 6.74V I think but it all happend fast and when I tried again I got 3.99V every time I measured.

Update:

I had some time and compared voltages between the working cores and not working. After 3rd power up I get a ready message from Core2!! I have now got it 3 times in a row. From voltage checks it seems that Core4 will not work since it has the same voltages at IC14 and IC25 as Core2 when it wasn´t working....now when Core2 works it has the same voltages as Core1 & Core3 (that is proven to work)

Here is the readings I got:

pin14: 

Core1: 3.23V (tested working)

Core2: 2.74V (tested not working) 3rd measure I get “ready†message and 3.23V here....

Core3: 3.23V (tested working)

Core4: 0.00V (not tested)

pin25 (Tx):

Core1: 5.16V (working)

Core2: 0.00V (was 3.99V last time I measured with midi cables to midistudio). 3rd measure I get a “ready†message!!! And 5.16V at IC25.....??!!

Core3: 5.16V (working)

Core4: 0.00V (not tested but probably not working....)

My newbines really shines through here. I have absolutly no clue to what is happening??? I´m still happy I have sound from it but please HELP:-)

I will continue tomorrow with checking out/reading about the octocoupler. It seems weird that core2&4 have exactly the same problem at pin14 and pin25...

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OK a few things:

There are no parts called IC14 or IC25... you're using this to describe a pin on a part but that's not how you do it... the real part I assume is U1_CORE1, U1_CORE2, etc. If in doubt, refer to the PDF of the PCB (http://www.mb6582.org/plans/MB-6582_Base_PCB_R2_Color.pdf) so you can tell us exactly which part and pin you are testing.

Pin 25 is the Tx pin. Depending on the position of a jumper in J11, that switches which of these pins is connected to MIDI Out.

When the PIC is not transmitting it will be 5V, when it is transmitting one "bit" it will be changing between 0V or 5V.

Pin 14 is one of the two pins connected to the crystal. I don't know that much about crystals, but I would assume the voltage there oscillates somwhere in the range 0V and 5V and is never constant. What you measure there will be an average, and probably affecting the oscillation (clock) so the PIC might not work.

You may have been confused by the MB-6582 testing instructions... Note I refer to testing pins 25 and 14 on the SID, not the PIC. The PIC pins to test are 11 and 12 (also forgot to add 31 and 32).

My advice:

Take the PIC that you know works in Core 1 and put it in the other Core "slots", and move the jumper in J11 to match (route that PIC's Tx pin to MIDI Out).

Power on, and look at MIDI In in MIOS Studio.

If you get the upload requests, then that PIC is booting up OK and MIDI Out is working.

Assuming it has MIOS installed already, if an LCD connected to that Core shows "READY." then that PIC is happy. Try sending it LCD display commands from within MIOS Studio to prove MIDI In works (all Cores are connected to the same MIDI In, but you can change "device ID" in MIOS Studio to address MIDI to a particular PIC, NOT a particular Core. So it makes no difference if PIC ID#0 is in Core 1 or Core 2, apart from what's connected to that PIC I mean...)

Run through those tests and report back.

And probably paranoid but please check you know pin ordering on an IC, so we're clear which pins you really are testing :)

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A couple of things...

The front panel:  are those the new Omron B3W pushbutton tactile switches?  They look nice.  And I kinda like the way the creme-coloured front panel looks with the wood cheeks.  To my eyes it's classier than black.

Solder joints:  first, a round solder joint is not necessarily an indication of a bad solder joint.  It really just means there's too much solder, and it's impossible to visibly inspect.  It's probably fine.  The real thing to watch for is bumpy or grey solder joints.  The thing is, a joint which would have been bumpy or grey can look nice and shiny if you use too much solder.  Getting that exact amount consistently is really a technique that takes some time to perfect, but your work looks excellent.  So don't sweat it.

As far as soldering MIDI connectors - if you have a temperature-controlled soldering station, and it includes a variable temperature, you really should be ramping up the heat for MIDI jacks.  Take a look at how thick and long those terminals are as they go up from the board into the connector.  Also take a look at the huge holes and pads they fit into.  All of that metal acts as a big heat sink, wicking heat away from where you're trying to solder.  Any time you get into the chunky metal, like jacks, heavy-gauge diode/rectifier/regulator leads, or wires you're trying to solder directly to a board, you probably want more heat than you would normally use for resistors or DIP sockets.

... And you are absolutely right:  DIY music electronics is a really great way to eat up your time.  It is extremely rewarding, but sometimes you need to step away from it all and make some music, with or without your homebrew toys!

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The front panel:  are those the new Omron B3W pushbutton tactile switches?  They look nice.  And I kinda like the way the creme-coloured front panel looks with the wood cheeks.  To my eyes it's classier than black.

Yep, Omron B3W switches. They were way expensive but as I didn´t need that many it was ok. I haven´t tried them yet but they look great! The front panel is acutally just a testdummy made from plastic. I was thinking black for the real one :) or maybe alu coloured.

Thanks nebula for soldering tips! I´m getting more and more confident soldering and I think it´s great fun and kinda relaxing. I´ve noticed the problem soldering those big things and I´ll try to turn up the heat some on those. And yes, might soon be time to make some music again but first I need to get my sid up and running;-)

Many thanks for your help Wilba! I don´t know why I wrote “IC†and not “picâ€...it´s the pin numbers on the PIC I´m refering too as you guessed :) I tried to take out the PICs again but decided to wait until I get a IC-puller so I don´t trash them (to tight to get a small screwdriver between the socket and PIC)

In the meantime I will try to explain my steps so far a bit clearer. I tested the pins in the mb6582 manual before I put any pics in and they all was ok (5.18V). I then put in a PIC in U1_CORE1 and got a “readyâ€. I also uploaded the MB6582 app and a 6582A in C28_SID1 and got sound out of it! Very very encouraged by this I took water above my head and put in a PIC in U1_CORE2 and U1_CORE3. I hooked up my LCD to J15_CORE2 but only got blocks. I also tested the lcd in U1_CORE3 and got a “ready†message.

Then I started a random troubleshooting (newbie as I am;-)) At first I didn´t think it would have anything to do with midiconnections since it worked with the pic in U1_CORE1 but I tested the pins in the midi troubleshooting guide and then got different voltages for the working U1_COREs (1 & 3) and the not working U1_CORE (2 & perhaps 4). Here is the voltage results with no jumper in J11:

U1_CORE1

Pin1:  5.18V

pin11: 5.18V

pin12: 5.18V

pin14 (OSC2): 3.05V

pin20: 5.13V

pin25(Tx): 5.17V

pin26 (Rx): 5.18V

pin31: 5.18V

pin32: 5.18V

U1_CORE2

Pin1:  5.18V

pin11: 5.18V

pin12: 5.18V

pin14 (OSC2): 2.74V (3.23V after some tests when the pic started working!)

pin20: 5.13V

pin25(Tx): 2.74V

pin26 (Rx): 5.19V

pin31: 5.19V

pin32: 5.18V

U1_CORE3

Pin1:  5.18V

pin11: 5.18V

pin12: 5.18V

pin14 (OSC2): 2.49V

pin20: 5.13V

pin25(Tx): 5.16V

pin26 (Rx): 5.18V

pin31: 5.18V

pin32: 5.18V

U1_CORE4 (with no PIC)

Pin1:  5.18V

pin11: 5.18V

pin12: 5.18V

pin14 (OSC2): 0.00V

pin20: 5.13V

pin25(Tx): 0.00V

pin26 (Rx): 5.18V

pin31: 5.19V

pin32: 5.18V

Some things I noticed: the voltage for pin14(OSC2) drops for every U1_CORE (3.05V, 2.74V, 2.49V and 0.00V). The PIC in U1_CORE2 didn´t give a “ready†message today. I think it displayed the “ready†message for a brief moment when I did the voltage checks and messed around with the voltagemeter on the J4 pins. So it sort of comes and go. When it worked 3 times yesterday it once rebooted with power still on. I´m also a bit worried about the 0.00V on U1_CORE4 Pin25(Tx)....U1_CORE4 is the only one without the PIC in it maybe that explaings something?? I also did some random voltage checks and only thing that made me wonder if it´s right was 13.49V on J25.

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Some things I noticed: the voltage for pin14(OSC2) drops for every U1_CORE (3.05V, 2.74V, 2.49V and 0.00V). The PIC in U1_CORE2 didn´t give a “ready†message today. I think it displayed the “ready†message for a brief moment when I did the voltage checks and messed around with the voltagemeter on the J4 pins. So it sort of comes and go. When it worked 3 times yesterday it once rebooted with power still on. I´m also a bit worried about the 0.00V on U1_CORE4 Pin25(Tx)....U1_CORE4 is the only one without the PIC in it maybe that explaings something??

Hi Jooks.

I have never tried to measure the voltage across a crystal. Whatever it is on this one will be oscillating 10 million times a second so you will never get any useful readings with a standard DVM (if you had a 10Mhz oscilloscope you might see something useful). For this sort of test I would turn off the power and check the continuity between the PIC pins and the crystal, this should be enough...

With U1_CORE4 Pin25, you answered your own question, the clue is in the pin name, Tx (Transmit) if there is no PIC in the socket then it can't be transmitting anything! I would expect the Tx pin to be around 5v when it isn't doing anything (if there is a PIC in the socket!)

I would be a bit worried if getting a "READY" message is intermittant, that indicates a possible bad (dry) connection.

Cheers

Phil

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Hi Jooks.

I think you added the bit about J25 while I was replying as I didn't notice it before :)

Have you tried a forum search? I just did a quick one and J25 is an unregulated DC output for a 'fan'. It should be between 9v and 11v so 13.49v does seem a wee bit high, what power supply option are you using? If you are using one with regulators on the MB6582 then I would check that these voltages (5v and 9v as you are using 6582 SIDs) are correct....

Phil

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Thanks for helping Phil! Makes sense with Tx :) I feel a bit better now. But the intermittent "ready" message from U1_CORE2 is worrying I admit.

I have never tried to measure the voltage across a crystal. Whatever it is on this one will be oscillating 10 million times a second so you will never get any useful readings with a standard DVM (if you had a 10Mhz oscilloscope you might see something useful). For this sort of test I would turn off the power and check the continuity between the PIC pins and the crystal, this should be enough...

I have continuity for all pin14 - Q1_Core - C2_CORE so that is ok. I still think it´s odd that the voltage drops for every CORE....even if it´s not a true value the steady drop from 3.05V down to 0.00V seems to reflect some trouble. With 0.00V at PIN 14 I can´t expect U1_CORE4 to work I guess?

Have you tried a forum search? I just did a quick one and J25 is an unregulated DC output for a 'fan'. It should be between 9v and 11v so 13.49v does seem a wee bit high, what power supply option are you using? If you are using one with regulators on the MB6582 then I would check that these voltages (5v and 9v as you are using 6582 SIDs) are correct....

I´m using a C64 power supply (1.7A version for "newer C64). It´s the version with only 4 pins but that is fixed in the revision 2 MB6582 board. I have PSU option B for MB6582 so I have 3 regulators on the board (7805, 7809, 7812) I have checked 5V, 9V and 12V on J4 and they are 5.20V, 9.05V and 11.90V. I have also checked all C8/C28_SID sockets and they are fine at the testing pins with both 9V and 12V. Is there any other place I can measure for more info? Could it be a bad power supply? I have another C64 supply (older version). Might try that instead.

/erik

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I have PSU option B for MB6582 so I have 3 regulators on the board (7805, 7809, 7812) I have checked 5V, 9V and 12V on J4 and they are 5.20V, 9.05V and 11.90V.

/erik

I don't know if it's precisely related to your problem but option "B" has no 5V regulator because the 5V output from the C64 is regulated already.

http://www.midibox.org/dokuwiki/doku.php?id=wilba_mb_6582_base_pcb_construction_guide&s[]=6582

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I don't know if it's precisely related to your problem but option "B" has no 5V regulator because the 5V output from the C64 is regulated already

You are right! I wrote without checking what I actually had... I have 2 7809 and 1 7812 on the board so that should be ok.

Btw. I searched and found that 13.49V on J25 is probably nothing to worry about since it´s unregulated 9V+5V.

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As nebula said, the 7805 you mounted will not be connected to anything because that is not supposed to be mounted in PSU Option B.

Basically you need to take out all ICs (except 6N138 optocoupler) and only put in one PIC on the board at one time.

Since you know the PIC is good in Core 1, you can then test what is different when you put it in Core 2, 3, 4 etc.

Once you are able to put the "known good" PIC (with ID #0) into Core 2, you can test MIDI In, change the jumper in J11 to test MIDI Out, test LCD etc. Get Core 2 going first, then move on to Core 3 and then Core 4.

Good troubleshooting involves testing what you know works in something that doesn't, in this case, moving the working PIC into other Cores. Then you can find the problems, in this case, it is probably bad solder joints in that Core, but it could be other things. It also makes things easier for people helping you because you only need to report what does and does not work with one small chunk of the problem (i.e. one Core). What you learn fixing one Core will probably help you fix the other Cores by yourself :)

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As nebula said, the 7805 you mounted will not be connected to anything because that is not supposed to be mounted in PSU Option B.

I have no 7805 mounted (it was a misspelling) so that should be ok.

Basically you need to take out all ICs (except 6N138 optocoupler) and only put in one PIC on the board at one time.

Since you know the PIC is good in Core 1, you can then test what is different when you put it in Core 2, 3, 4 etc.

I will do this asap when I get the IC-puller. I don´t want to force the PICs out and destroy them (I tried some with a screwdriver and it didn´t feel great).

I´m sorry my troubleshooting is a bit random....but since I have to wait some days before I can pull the PICs is there a way the PICs can have something to do with the varying voltages or the intermittent "ready" message from U1_CORE2?

Many thanks for the help :) I still have good faith that this will be ok in the end with the great support :)

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Ok, thanks! Actually I got the puller today (ordered yesterday afternoon!!) so my weekend is saved :)

I´ll probably try to go over the solderjoints first and then try the different cores with the proven PIC like you have guided me Wilba.

I don´t know if this is any usefull info but I tried the other power supply and got some different readings. Still not 100% correct but IC14 voltage was about 1.1V for all cores (didn´t drop for each core like with the other supply) except U1_CORE4 (which still was 0.00V) I´ll post the readings later.

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Hi Jooks.

I would really ignore what voltage you are seeing on PIN14. You will only see ANY voltage on here if there is a PIC in the socket but you could easily interfere with the PIC operation (and even crash the PIC) by putting a meter on this pin.

As Wilba suggested, definately remove all chips and then measure voltages again. As these are all fairly fragile, it is always a good idea to do this before you put any of the chips in!

Cheers

Phil

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I would really ignore what voltage you are seeing on PIN14. You will only see ANY voltage on here if there is a PIC in the socket but you could easily interfere with the PIC operation (and even crash the PIC) by putting a meter on this pin.

oops, I´ll stay away from the pin14 then! I don´t think I´ve damaged anything though still get good messages from PICs in CORE1 and CORE3.

I will pull the PICs tomorrow and go over the joints. I measured the voltages recomended in the MB6582 manual and it was all ok but I´ll do it again and see what happens. Then some PIC crosschecking. Thanks again :)

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After more thinking, an LCD that is intermittent between black bars and "Ready" means that the PIC is sometimes controlling the LCD and sometimes not (black bars mean LCD has power but not receiving commands). So it could be either PIC->LCD connections are faulty, and/or the PIC is not booting up, perhaps caused by bad joints to reset pin (pin 1), crystal oscillator pins, power supply (Vdd,Vss)... So a PIC might have good power connections but not actually be "working" due to those other pins, or be "working" but have some bad connections to the outside world (to LCD or to MIDI).

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Thanks Wilba for taking the time to help :)

I´ve removed all PICs and measured voltages and continuity again. I get the same readings for all COREs (5.20V on all measured pins except pin20 5.15V for all COREs). I tested continuity for all pins at U1_CORE2 and no problem there (I followed the lines at the Mb-6582 pdf). I´ve also tested ohms for resistors is ok. I´m fumbling in the dark here so excuse me if my questions is strange but can it still be a bad joint somewhere on U1_CORE2 causing the intermittent "ready" message when all pins have continuity and the right voltages (without the PIC)?

In my newbie thinking I´m thinking maybe the crystal is bad or the PIC? Or a cold joint? I guess I can only continue troubleshooting by inserting the "working/non-working PICs" in different COREs..I will go over the joints first though..

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Ok, I had some time and resoldered (added som heat) the joints in the non-working U1_CORE2 I thought might need it. Then I inserted the working PIC (#0) in every CORE. Result: working LCD message (loaded MB6582 app) in U1_CORE1/3/4. Black bars in U1_CORE2.....just like before :(. At least this might rule out that there´s anything wrong with PIC#01?

I didn´t have my laptop so I couldn´t test midi in/out for different COREs. Will do that later and report.

Result for voltage test:

U1_CORE2

Pin 1: 5.20V

Pin 11: 5.20V

Pin 12: 5.21

Pin 20: 5.15V

Pin 31: 5.21V

Pin 32: 5.21

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OK the next step would be to test MIDI for Core 2, to prove the PIC is actually working in that Core and that the problem is just the LCD connection.

You can easily prove MIDI works by moving the jumper in J11 to position 2 (so Core 2 Tx is connected to the MIDI Out socket).

Then watch MIDI In window in MIOS Studio when powering on the MB-6582. You should see only one bootloader upload request because MIOS and MB-SID app is installed. If that works, move on to testing MIDI In by trying to upload the app again - note it's still device ID #0 even though it's in Core 2 (application uploads go to the PIC with that ID, regardless of which Core it is in).

If those tests don't pass, then you'll need to fix MIDI first... it could be the PIC is not working because of bad connections to the crystal, the capacitors connected to the crystal (C1_CORE2,C2_CORE2)... missing ground connection to the Vss (ground) pins (pin 12,31)...

If the tests do pass, the PIC is fine, the Core is fine, it's just something wrong between the PIC and J15_CORE2 pins. Test connectivity between each PIC pin and what it's connected to in J15_CORE2. Also check that none of these are shorted with other nearby pins.

You can refer to this Core schematic to assist in connectivity tests:

http://www.ucapps.de/mbhp/mbhp_core_v3.pdf

Note PIC pins 35,36 are not connected to J15_CORE2 pins D2,D3, as this is a PIC18F4685 and only uses 4 bits to the LCD, and pins 35,36 are used for the CAN bus that connects the Cores together.

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Again many thanks Wilba :)

I tested midi out/in on Core 2 last time and got no upload request and could not upload anything but I will try again. I have also checked connectivity for all J15_CORE2 pins with no problems. I have not checked for shorts on those pins.

Note PIC pins 35,36 are not connected to J15_CORE2 pins D2,D3, as this is a PIC18F4685 and only uses 4 bits to the LCD, and pins 35,36 are used for the CAN bus that connects the Cores together.

Hmmm, I´m quite sure there was connectivity for PIC pins 35,36 and J15_CORE2 pins but maybe that´s how it should be? I will try again.

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Today I tested midi in/out with PIC#0 (proved to work) in core2. No signs of interaction in mios studio :( (no upload request in midi in monitor). When trying to upload the mb6582 hex from mios studio (smart mode) it doesn´t seem to upload anything but alot of numbers and letters in the midi out monitor (but it doesn´t say me anything really....kinda happy to see something though ;):

timestamp [unknown] | SysEx: F0 00 00 7E 40 00 02 0C 00 00 20 15 7B 63 3F
 04 6B 5E 1B 78 2B 5D 71 5F 42 6D 6F 0D 7C 1A 4E 78 6F 60 02 77 47 1E 05 3F 3C 
39 70 2E 3B 63 4F 02 13 5E 1C 78 12 3D 71 67 41 3F 6F 0E 3C 01 7E 78 73 60 0D 
77 47 1E 00 57 3C 39 70 06 3B 63 4F 04 03 5E 1A 78 3A 3D 71 57 43 6F 6F 0D 3C 
1F 3E 78 6B 60 1C 77 47 1E 01 5F 3C 39 70 54 3B 63 2F 05 4F 5E 1A 78 3F 1D 71 
57 40 24 00 00 00 02 20 00 00 00 12 00 00 00 01 10 00 00 00 09 00 00 00 00 48 
00 00 00 04 40 00 00 00 24 00 00 00 1F 7F 79 69 0B 10 00 0D 48 59 08 00 64 45 
49 00 05 64 2C 4C 00 2A 22 65 00 0F 32 12 46 00 7D 11 34 00 04 59 11 18 00 38 
48 49 48 03 1C 44 4D 00 16 64 44 6C 00 50 22 62 60 05 22 16 14 00 2C 11 31 10 
02 71 0B 08 00 21 48 68 00 00 1C 46 40 40 03 24 34 08 00 30 23 20 60 09 12 1A 
74 00 24 11 77 70 00 01 0F 39 00 09 08 7B 58 00 7C 48 5E 40 0A 64 45 78 00 6E 
24 25 60 09 02 1E 2A 00 57 11 73 60 06 41 0F 3C 00 0B 09 09 30 01 58 46 4E 40 
1C 04 40 1E F7

I also (again...) tested voltage with PIC in core2

pin1: 5.20V

pin11: 5.20V

pin12: 5.20V

pin 20: 5.15V

pin 25: 4.05V

pin26: 5.20V

pin 31: 5.20V

Pin32: 5.20V

Still fumbling in the dark....midi for core2 doesn´t seem to work for some reason but I guess voltages seems ok (or?) pin25 tx: 4.05V must indicate some sort of action but maybe not the right kind of action?

If those tests don't pass, then you'll need to fix MIDI first... it could be the PIC is not working because of bad connections to the crystal, the capacitors connected to the crystal (C1_CORE2,C2_CORE2)... missing ground connection to the Vss (ground) pins (pin 12,31)...

I tested connectivity crystal/capacitors C1/C2_CORE2 and pin 14 and pin 15 and that is ok. I also tested ground (vss) to pin 12 and 31 and that is also ok.

I think the solder joints look as good as any other and I´ve tried to resolder (mostly reheat) the ones I thought needed it. Not sure what I can do next here....bad crystal or capacitors?

I´m very greatful for all help :)

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At this point, it seems likely that the PIC is not booting/running at all in Core 2, therefore you're not seeing the upload request in MIOS Studio and also not seeing anything on the LCD (i.e. a "Ready" message from MIOS installed on the PIC).... and that it's probably something to do with the crystal and/or capacitors C1_CORE2,C2_CORE2.

Do all the following, reporting results:

check there's really a 10Mhz crystal installed.

check there are 33pF capacitors installed in C1_CORE2,C2_CORE2

it's possible that there's a bad joint on the ground pins of C1_CORE2,C2_CORE2 (the two pins which are closest to each other).

check again connectivity between the crystal pins and both the PIC pins and the capacitor pins they connect to, also checking none are shorted to each other, any nearby pins, or ground (except one pin of each capacitor which should be grounded).

check PIC pin 25 is not connected to pin 24 or pin 26,  and is connected all the way to the bottom pin of R27 (the 2nd resistor to the right of the mount hole below the MIDI Out socket). Obviously J11 will have to have the jumper in position 2 for this to happen.

I still think it's a soldering mistake somewhere, so I don't really want to suggest replacing the crystal or C1_CORE2,C2_CORE2  capacitors just yet... but obviously doing so might prove they are not the problem. I would perhaps try desoldering and replacing the capacitors first. Go to your local electronics store and buy new 33pF ceramic capacitors, they are so cheap and it's a lot easier to cut the soldered one in half and desolder/remove one pin at a time. Perhaps buy one new 10Mhz crystal at the same time, also cheap enough to buy even if you don't use it. I am guessing here now, but maybe the capacitors were damaged while you soldered them (esp. the ground pin which is harder to solder and needs more heat)... that might explain good connectivity between everything but the PIC doesn't run at all so you don't see the MIDI or the LCD working.

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What would I do without you Wilba? Probably something less fun then building a MB6582 ;)

Here are the results from sweden:

check there's really a 10Mhz crystal installed.

check there are 33pF capacitors installed in C1_CORE2,C2_CORE2

Crystal says 10.000 (same as for the other cores, smash tv part kit)

33pF caps

it's possible that there's a bad joint on the ground pins of C1_CORE2,C2_CORE2 (the two pins which are closest to each other).

Both connected to ground (J4)

check again connectivity between the crystal pins and both the PIC pins and the capacitor pins they connect to, also checking none are shorted to each other, any nearby pins, or ground (except one pin of each capacitor which should be grounded).

Connectivity ok between crystal pins and pic/cap pins. No shorts to nearby pins.

check PIC pin 25 is not connected to pin 24 or pin 26,  and is connected all the way to the bottom pin of R27 (the 2nd resistor to the right of the mount hole below the MIDI Out socket). Obviously J11 will have to have the jumper in position 2 for this to happen.

No connection pin 25 to pin24/26. Pin 25 connected all the way to R7

I will put in new caps in C1/C2_CORE2 tomorrow and if still needed order a new crystal (no electronic shop here :()

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Just a small thing worth mentioning: Sockets are not to be ignored. When you test a PIC pin's connection to a trace, there are actually a few points you should test:

  • The joint where the trace solders onto the socket pin
  • The pin on the other side of the joint (underneath the plastic part of the socket)
  • The pin on the top side of the socket (where the PIC pin plugs in, above/inside the plastic part of the socket)
  • The PIC pin inserted into the above

Not only should you test for continuity, but if things seem a bit weird (which they do here) also test for resistance. It should be very low (theoretically it would be zero), and the same every time you test it. If it's a bit higher than other joints, or if it changes, you have a bad joint.

Sorry to interrupt, just wanted to make sure you're testing it right... Keep following Wilba's instructions :)

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