I have been building my first midibox project, the minimal SID, and I’m having problems already. I was hoping someone out there could help. Here is my setup:
18f4685 pic from smash as well as the core and sid boards
Sid ver R3A
Core ver R4D
6581 SID chip
and the simple (not optimized) psu version with parts from a c64
The story:
I tested all the voltages on both boards as directed, and found that everything was ok, I then plugged in the ic’s and tried out the core, and loaded in the sid application. Everything worked fine on the core except the backlight did not come on the lcd (but I could live with that). I was not getting any audio out of the sid (tried the test tone, then connection testing) and that failed. So I checked my connections from the core to the sid, (the sid was getting hot, so I knew something was going on…) then the c64 pwr supply went dead. I had another one handy, so I tried that one, and it worked for a while, then the regulator seemed to smoke a little (or was that my imagination?) and then everything stopped working again (fried power supply) I know this because I tried using it on my commodore computer, and it didn’t start up. I know I have done something stupid, but I just can’t figure out what… Checked all connections and soldering…The diagrams on the website for the connections are not the same as the version of the board I am using, so I had to make some educated guesses. Maybe that is were things went south.
Now I need to find some other way to power my project (all out of c64 power), I have a 12vdc 800ma transformer… Could I use that? If not any suggestions that I could find at radio shack? How do I wire them up? I haven’t seen any diagrams with info on how to hook up anything other than a c64 psu.
Well, thanks for reading my story, and I hope this hasn’t been covered ad nauseam, but I really have looked and tried, and now I’m stuck. I can’t wait to get this working!!
I have been building my first midibox project, the minimal SID, and I’m having problems already. I was hoping someone out there could help. Here is my setup:
18f4685 pic from smash as well as the core and sid boards
Sid ver R3A
Core ver R4D
6581 SID chip
and the simple (not optimized) psu version with parts from a c64
The story:
I tested all the voltages on both boards as directed, and found that everything was ok, I then plugged in the ic’s and tried out the core, and loaded in the sid application. Everything worked fine on the core except the backlight did not come on the lcd (but I could live with that). I was not getting any audio out of the sid (tried the test tone, then connection testing) and that failed. So I checked my connections from the core to the sid, (the sid was getting hot, so I knew something was going on…) then the c64 pwr supply went dead. I had another one handy, so I tried that one, and it worked for a while, then the regulator seemed to smoke a little (or was that my imagination?) and then everything stopped working again (fried power supply) I know this because I tried using it on my commodore computer, and it didn’t start up. I know I have done something stupid, but I just can’t figure out what… Checked all connections and soldering…The diagrams on the website for the connections are not the same as the version of the board I am using, so I had to make some educated guesses. Maybe that is were things went south.
Now I need to find some other way to power my project (all out of c64 power), I have a 12vdc 800ma transformer… Could I use that? If not any suggestions that I could find at radio shack? How do I wire them up? I haven’t seen any diagrams with info on how to hook up anything other than a c64 psu.
Well, thanks for reading my story, and I hope this hasn’t been covered ad nauseam, but I really have looked and tried, and now I’m stuck. I can’t wait to get this working!!
All the best,
Jordan
Oh, one more thing… There was a low hum on the audio out when the core was working (before I fried the psu’s)
Hi Jordan. My name is also Jordan. Therefore I feel some solidarity.
I don’t want to alarm you, but it’s possible you’ve blown out your sid and/or pic. Absolutely do not plug any more power into the board until you get this figured out.
I know you already did this, but I think you should perform the voltage tests again. If the regulator was actually smoking, that clearly indicates a short somewhere between power and ground. Hopefully you haven’t also burnt out your sid… they do get pretty hot under normal operation (the 6581’s especially) so it’s hard to tell if the heat was from a critical failure or not. We won’t know till we can get some sound out of it.
If you can take some pictures of your boards (including your power board!), that would greatly help in troubleshooting this.
I suspect your PSU circuit/wiring was off… Here’s your 10-step program to happiness:
Take decent pics of everything and post them here
NO MORE POWER/ICs ON THE MODULEs UNTIL YOU FOUND THE PROBLEM
Remove all ICs
Disconnect the LCD
Disconnect the boards from each other
Power up the core and make measure all voltages. Post them here
Unplug the power
Connect the SID module to the Core module
Plug in the power to the Core modul and check for the 5V on the SID module
Add the power supply for the SID, measure voltages.
Report back with the results
For testing purposes(!) you can use that 12VDC wallwart IF and only IF it is regulated (ie delivers a constant perfect 12V). If that’s the case you can simply wire it to the core’s J1 for the core power (do not use the LCD with it for now because too much current draw will give you a pretty hot regulator), and also wire it directly to the output pins of the 7812 on the SID module (ground to pin 2, 12VDC to pin 3, see http://ucapps.de/mbhp/mbhp_sid_v3.pdf).
Thank you for your much needed input (and yes, us Jordan’s have to stick together!).
I followed all the steps listed, and got confirmation that at least the PIC is alive! Bootloader is up and running. I had the test tone loaded, but there was no sound from the audio out except a heartbeat type sound that coincided with a midi event on the “in” side of mios studio it reads “f0 0000 7e 40 0001 f7” over and over again… I tried to load the sid program, but it was taking for ever and finally failed, as it seemed to be loading each line in between each “heartbeat”. Needless to say my wife thought things were pretty weird when she saw me operating on the midibox with a heartbeat!.
Here is the new info:
I tested the walwart that I had lying around, and it was giving be more like 18v at 800ma, so I bought a 12v 300ma regulated walwart and tested it at a steady 12v
made a switch and sent power to both the core(J1) and the sid(at the regulator), wasn’t too sure about Core (J2) and vs and vc or sid(J2) (one says vs vd, the other vc vs) but I connected them together vs-vs vd-vc
took all the chips out and checked all voltages, and they were all at 5v
put all the chips back in and tested for sound… just the heartbeat sound.
I decided to check the voltage at the regulator (from the wires) and it was all over the place, not 12v, not even 7v just jumping around.
I have attached a picture, I scrapped using the psu I built, so I’m just using the switch on the left.
The f0 0000 7e 40 0001 f7 is no cause for alarm, this is simply the core outputting an upload request. It’s odd that it corresponds to throbbing noises from your sid however!
One thing that stands out right away is you shouldn’t be using core J2 for anything. the 5 volt line to the SID board is supplied from core J10.
You should have a 1-to-1 connection between core J10 and SID J2. Looking at the schematics I’m actually not sure if there’s much of a difference compared to how you have it wired, but it’s better to do things by the books.
Also, the “heartbeat” could be indicative of the sids not receiving power properly… Just to clarify, the sid module needs two different voltages: a 12 volt line that powers the sids themselves, and a 5 volt line driving the other ICs. Double check the power running to the sids… did you directly connect the 12 volt output of your PSU to pins 2 and 3 of the voltage regulator as nILS outlined?
If yes, that schematic will only work if you don’t have the voltage regulator on the core stuffed. The crucial thing to understand is that core J1 lives upstream of the voltage regulator, and core J2 lives downstream (see the bottom right corner of this schematic: http://www.ucapps.de/mbhp/mbhp_core_v3.pdf ). Core J1 feeds power through the bridge rectifier, big filtering caps and the inputs of the 7805. Core J2 is meant to supply other boards with the regulated output of the 7805. Since the regulator is unstuffed in the optimized psu, power can be supplied directly through Core J2, bypassing all the power related components on the top of the board. If you are powering your core through Core J2 directly from your 12v PSU however then you are way exceeding the voltage requirements of the core.
You want to be feeding the core through core J1. You should then power the sid module through vs and vd on core J10 (as smash recommends in his build guide here: http://www.avishowtech.com/mbhp/mbhp_SIDR3a.html ). Unless you’re using the optimized psu, J2 shouldn’t be used as a power input.
Edit: after scolding you on your links, mine were broken! :rolleyes: They’re fixed now.
Sorry about the link problem, not sure what happened…I was going off the mbhp_sid_c64_psu.pdf on the SID build page, so not the optimized version.
So I won’t use the core J2, and I’ll connect vd and vs of the core to vc and vs on the SID board.
I’ll report back success/failure
Thank you so much for taking the time to help me.
Jordan
No problem man, I hope we get you closer to a working MB.
looking at mbhp_sid_c64_psu.pdf (which I never looked at before!) I see now where this j2 business comes from. If you wanted, you could continue to supply sid j2 with core j2, so long as you’re powering the core through j1 with regulator stuffed. This all leaves the question open however as to what caused your explosion to begin with, if you had everything wired according to the schematic and used a c64 PSU. Perhaps someone smarter than me could chime in here.
Just tried it, with no difference. I’m still getting the heartbeat and everything…
Applications take a long time to upload, and there is an error when I try to upload something big like the SID application. I’m sure that I am doing something really silly and noobish! The md pin on core J10 is still unused, and when the whole system is turned on the SID and regulator don’t get hot at all. Can I go to J1 Sid power instead of directly to the voltage regulator 7812? I was hoping that there would be some kind of hook up diagram on the Smash site to hook up the core and SID modules… but I guess there are a lot of different ways to do it.
When I remove the ic’s and check the voltages they are all fine, with 5v at the IC’s and 12v at the sid regulator.
Should i use a separate power supply for the core, and 12v Sid?
Okay, it seems there’s a problem with your interconnection between j10 and j2. It should be wired like this:
J10 J2
MD -> SC
MU -> MU
CLK -> CLK
VD -> VC
Vs -> Vs
SO -> SO
RC -> RC
SC-> Nothing! (it’s not used by the SID module)
You can use these two images as a guide, as I’ve said the connection should be 1-to-1 (physically, pin one should go to pin one, 2 to 2, etc, the labeling doesn’t necessarily line up!)
Can I go to J1 Sid power instead of directly to the voltage regulator 7812?
Not unless you remove the voltage regulator and the bridge rectifier. Supplying power at j1 will feed into the inputs of the 7812 through the rectifier, which won’t work using your 12v PSU (voltage regulators require a few volts above their regulation to work, and the rectifier causes an additional voltage drop, meaning you would be supplying the 7812 with something like 11 volts when it wants 14-15 volts). Connecting your psu to j1 won’t hurt anything, but no power will make it to the sids.
Not unless you remove the voltage regulator and the bridge rectifier. Supplying power at j1 will feed into the inputs of the 7812 through the rectifier, which won’t work using your 12v PSU (voltage regulators require a few volts above their regulation to work, and the rectifier causes an additional voltage drop, meaning you would be supplying the 7812 with something like 11 volts when it wants 14-15 volts). Connecting your psu to j1 won’t hurt anything, but no power will make it to the sids.
This seems like something I should be double checking… I’ve connected the regulator on the SID (pins 2 and 3) marked In and vs and I am getting 12v when there are no ic’s present.
But when I have the ic’s in and everything is functioning I get erratic readings at the regulator. Jumping around .5 to 1 to at the most 3v. This has got to have something to do with it because the SID won’t have enough power to operate. Am I correct?
Well, I’m sure that was part of the problem, but I changed the connections and tested them with the meter. But same thing…
There is no heat at the chip or regulators, and the upload request is ticking along. Maybe my power supply is not strong enough (12v 300ma)?
Again, thanks for the help. Once I get this organized, I’m going to add a controller, then some more sids. But I’ve got to at least master this first
Jordan
It’s possible. I’m not sure how much current the SId is sinking but it’s probably between 50 and 100 ma. Smash recommends supplying the core with a 500ma supply, though this is with a backlit LCD attached. It certainly couldn’t hurt to try a higher rated supply. If you’re planning on building a full control surface later, you’ll need something in excess of 1A anyway, so it might make sense to just invest in that now. I’m using a 2A supply with my midibox sid.
This seems like something I should be double checking… I’ve connected the regulator on the SID (pins 2 and 3) marked In and vs and I am getting 12v when there are no ic’s present.
But when I have the ic’s in and everything is functioning I get erratic readings at the regulator. Jumping around .5 to 1 to at the most 3v. This has got to have something to do with it because the SID won’t have enough power to operate. Am I correct?
Jordan
Yes, this definitely should not be happening. It’s hard to tell exactly what would cause this behavior without being able to closely inspect your setup, but it could simply be that your PSU is sagging when under load, in which case swapping it out for a higher rated supply is the way to go. There’s a couple things that make me think this might not be the issue however, one of which being the upload request - which means the pic is getting power. However, since you’r getting errors trying to upload hex files, perhaps the voltage is just fluctuating all over the place and the core is sporadically rebooting. :ermm:
