FV-1 Multi effect full forum project ready to go. (ShimmerVerb Also)

[potul]

SMD is looking good, parts list sub R2 33R with a jumper. I will have a look to see if I can replace the schematic and layout pictures that have gone due to Photobucket.

Sorry folks,... some more questions as I move on populating the pcb. If I don't use the mosfet and use standard diode protection, should I populate R2 or sub it with a link as stated above?

[Ice-9]

Quick question... as this is not in the schematic

In the PCB, at what voltage is the LED powered? is it getting the full 9v or 3.3v?  I need this in order to decide the limiting resistor value... (I assume it's getting the 9v, just want to double check)

Mat

LED is wired to 9v with a limiting resistor in series to the footswitch to ground.

[Ice-9]

SMD is looking good, parts list sub R2 33R with a jumper. I will have a look to see if I can replace the schematic and layout pictures that have gone due to Photobucket.

Sorry folks,... some more questions as I move on populating the pcb. If I don't use the mosfet and use standard diode protection, should I populate R2 or sub it with a link as stated above?

R2 should be replaced with a wire link in both configs, but check what you need to do to replace the mosfet, I don't have the circuit to hand at the moment but it will depend  on what config of standard diode protection you want to use as to what needs altered with other wire links. Diode to ground or diode in series ?

[potul]

Thanks for the help... I've already figured it out and now I have it powered.

So, I've finished the build, and as expected I'm having a big issue. I did not have a test socket when I did the smd soldering, so I did not program the eeprom before soldering... I programmed the pic only.
Now I'm trying to write to the eeprom without success. I'm not able to communicate with it.

Today I received a test socket.... I tried to flash the memory (another one I have) outside of the pcb and it worked fine, so the pickit and software works.

But, when I try to program it at the pcb, I get an error. Same error I get if I don't connect anything to the pickit.
I verified that pin 8 is having 3.3v, pins 1-4 and 7 are grounded, and pins 5 and 6 are connected to the pads under the pcb correctly.

Any hint on what can be happening? Maybe the eeprom is damaged during soldering?

PS: The PIC is working fine, I can see the gpios change status when moving the pot. I don't know if the FV-1 works because I have no program in the eeprom.

[lietuvis]

You can ground pin 13 and have internal patches active to test FV-1.

[potul]

You can ground pin 13 and have internal patches active to test FV-1.

I thought on doing this, but pin 13 is already connected to vcc, .... I would need to lift it first.  It's a good option if everything else fails.

[potul]

Ok, I'm narrowing things down . I've been able to program the EEPROM on board. The  weird thing is, in order to do so I had to add the pull up resistor to SDA pin of the memory. I was under the impression this was not needed when in the pcb because there was already a pullup.
Looking at the schematic, SDA pin is only connected to FV-1, so I suppose when in the pcb, the pullup is done via the FV-1. But in my case this was not working...

So now that my eeprom is programmed and verified, I get no sound of the FV-1. When in bypass the signal comes through, but as soon as I engage, nothing comes.

Havind had this issue with the SDA pullup, I'm starting to suspect either the memory is not connected properly to the FV-1, or the FV-1 is dead...

I have to leave it for today, ... this weekend I will try to do some more debugging.

[Ice-9]

It will be worth reading the EEPROM with the programmer to see if data has actually been written correctly to the chip, also try to verify the data on the EEPROM via the pickit2. If I remember correctly it may also program best with the pedal connected to its power supply.

EDIT- I see you said the EEPROM is verified , I miss read that.

Can you audio probe the signal up to pin 1 of the FV-1 to make sure the audio is ok to this point ?

[potul]

It will be worth reading the EEPROM with the programmer to see if data has actually been written correctly to the chip, also try to verify the data on the EEPROM via the pickit2. If I remember correctly it may also program best with the pedal connected to its power supply.

EDIT- I see you said the EEPROM is verified , I miss read that.

Can you audio probe the signal up to pin 1 of the FV-1 to make sure the audio is ok to this point ?

This is going to be my first step once I restart debugging...

[Ice-9]

It will be worth reading the EEPROM with the programmer to see if data has actually been written correctly to the chip, also try to verify the data on the EEPROM via the pickit2. If I remember correctly it may also program best with the pedal connected to its power supply.

EDIT- I see you said the EEPROM is verified , I miss read that.

Can you audio probe the signal up to pin 1 of the FV-1 to make sure the audio is ok to this point ?

This is going to be my first step once I restart debugging...

I will keep an eye open on this thread over the weekend in case I can help.

[potul]

Changing topics..... would this work as a program selector without PIC?

http://www.ebay.com/itm/Panel-Switch-x2-BCD-3-bit-binary-encoding-numeric-readout-push-button-advance-/172775100051


Wouldn't it be cool?

[lietuvis]

Changing topics..... would this work as a program selector without PIC?

http://www.ebay.com/itm/Panel-Switch-x2-BCD-3-bit-binary-encoding-numeric-readout-push-button-advance-/172775100051


Wouldn't it be cool?

Yes it should work but won't fit under pcb in 1590b. I have used one of this http://www.ebay.co.uk/itm/16-way-Rotary-Switch-ITW-16-412/272606168569?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649 on my build where I use built in effects and its fitted on pcb but access from bottom of enclosure

[potul]

Yes it should work but won't fit under pcb in 1590b. I have used one of this http://www.ebay.co.uk/itm/16-way-Rotary-Switch-ITW-16-412/272606168569?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649 on my build where I use built in effects and its fitted on pcb but access from bottom of enclosure

Nice.... I didn't think about it... so in fact by connecting the extra bit to the FV-1 internal/external selector you can access all 8 internal and 8 external patches with a single selector.  I was thinking on an additional switch, but this solution looks better.

If only they could be shafted ones ...

PS: Your pictures are not showing.

[lietuvis]

PS: Your pictures are not showing.
[/quote]
I can see them on my browser, here is link : https://www.dropbox.com/sh/dw093djpsbqn5vk/AADdnvfQLO4WZfNNIRWJfXnVa?dl=0

[Ice-9]

The PIC chip can also be programmed with a 4 bit counter code to select the internal programs, this would require the int/ext pin of the fv-1 to be lifted and connected to the pic, this would work perfectly with a pot to control the program changes but if a switch was required a 16 way switch would need to be used, I couldn't find a 16 way switch small enough to use

I did find pots with click indents which would have been great but I could only find them with 11 indents. Boss use this type of pot for program selection on the RV6 reverb pedal.

[potul]

The PIC chip can also be programmed with a 4 bit counter code to select the internal programs,

mmm, I didn't think about it. That's a good solution as well if the PIC  has a free I/O. Maybe in the next build... I need to make it work first as stock.

Mat

[lietuvis]

Hi here is another way to do program selection I found on web and tested and it works by using pic16f628a + 7 segment led indicator and using two buttons: up and down. find files in this link https://www.dropbox.com/sh/2keba7bngtucmkz/AACAtZDUPWDpqP1bNSVe-Jrpa?dl=0

[Ice-9]

Hi here is another way to do program selection I found on web and tested and it works by using pic16f628a + 7 segment led indicator and using two buttons: up and down. find files in this link https://www.dropbox.com/sh/2keba7bngtucmkz/AACAtZDUPWDpqP1bNSVe-Jrpa?dl=0

Yeah , I wrote the 7 segment up/down code for PIC16f628a and it is posted somewhere here or on the other popular pedal forum, the full schematic should be there as well. 

[potul]

Ok, finally after a busy week I had the time to look more into my issue...

Definitively the issue is at the FV-1. Audio is hitting the FV-1 input, but no output out of any of the outputs. And if I inject audio at the output pin of the FV-1, it reaches the output jack (so the output part works as well)

Now, what things can I test to see why the FV-1 is not working properly? Things that come to my head:

1-Verify FV-1 received the right power and ground - DONE
2-Lift up the T0 in FV-1 to user internal programs -> I prefer to do this only as a last resort
3-Verify the crystal is oscillating. - Any idea how to do this?
4-Verify the communication from FV-1 to eeprom. Any suggestion how to do this?
5-Reprogram the eeprom with a simple bypass program (just in case the hex file was not good... but I used one file published here in the forum for the project, it should be ok...)

I have a USB scope I can use for troubleshooting.
I prefer non-destructing tests first.. as de-solder and solder the FV-1 at this stage when everything else is soldered is going to  be a pain.

Regards

Mat

[slacker]

Are you getting about 1.65 volts on pins 1,2,3, 27 and 28?

You can test for communication between the FV-1 and the eeprom by probing the SDA and SCK pins with your scope, at startup and when changing programs you should see brief bursts of activity on both pins.
You can try probing the x1 and x2 pins to see if the crystal is working, you should see about a 32KHz signal, this isn't a very good test though because the extra capacitance from the probe could be enough to make it start working or it could load it down and stop it working.