DIY Mutable Unsuccessful Builds

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Wed Jun 10, 2020 2:06 pm

forestcaver wrote:
Wed Jun 10, 2020 12:44 pm
Any reason for mounting the jtag connector on the component side? That’s going to make some interesting wiring to get the right pinout for the stlinkv2..... :-)
I have actually desoldered one once with a hot air gun.

Desoldering the holes left is another matter, it makes you understand the physics classes about surface tension! :-O

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Re: DIY Mutable Unsuccessful Builds

Post by soupspoon » Wed Jun 10, 2020 2:26 pm

cnicht wrote:
Wed Jun 10, 2020 2:01 pm
soupspoon wrote:
Wed Jun 10, 2020 9:50 am
cnicht wrote:
Wed Jun 10, 2020 4:33 am
I presume you're referring to a Plaits build?

Have you placed the jack sockets?
Yes, sorry! Totally forgot that information. I have placed everything on the PCB, including the jacks.
Is there any signal coming out of the DAC?
Not so far as I can tell. I reflowed it again and checked, but still no output. I'm measuring on pins 6 & 7 (designated on the datasheet as OUTL and OUTR).

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Wed Jun 10, 2020 2:36 pm

You should see an attenuated output signal on these pins.

Is the DAC generating its own negative voltage?

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Re: DIY Mutable Unsuccessful Builds

Post by funketek » Wed Jun 10, 2020 2:40 pm

whew..

Kind of an embarrassing mistake, but thank you for being gentle!

Looking forward to de-soldering the jtag. :doh:

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Re: DIY Mutable Unsuccessful Builds

Post by soupspoon » Wed Jun 10, 2020 2:47 pm

cnicht wrote:
Wed Jun 10, 2020 2:36 pm
You should see an attenuated output signal on these pins.

Is the DAC generating its own negative voltage?
I'm measuring >0.1V on the VNEG pin (pin 5).

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Wed Jun 10, 2020 2:49 pm

It should be -3.3V

Check DAC soldering

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Re: DIY Mutable Unsuccessful Builds

Post by soupspoon » Wed Jun 10, 2020 3:24 pm

cnicht wrote:
Wed Jun 10, 2020 2:49 pm
It should be -3.3V

Check DAC soldering
I did continuity checking for the board and checked the Vdd pins. The supply voltage pins are reading a constant 3.3V, and I couldn't find anything obviously wrong. I have a 30x magnifier and I don't see any bridges on the pins, so I'm not sure what's going on. Any ideas where to look?

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Wed Jun 10, 2020 3:40 pm

The DAC May be in sleep mode if it's not receiving the correct signals.

An issue may be the voltages at the outputs of the op amps which condition the signals from the input jacks, and the presence of the normalisation signal.

Check all these are present and correct.

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Re: DIY Mutable Unsuccessful Builds

Post by soupspoon » Wed Jun 10, 2020 4:43 pm

cnicht wrote:
Wed Jun 10, 2020 3:40 pm
The DAC May be in sleep mode if it's not receiving the correct signals.

An issue may be the voltages at the outputs of the op amps which condition the signals from the input jacks, and the presence of the normalisation signal.

Check all these are present and correct.
The op-amps have the proper supply voltages (3.3V and 0V). No obvious bridging on the pins, and the attached components read properly according to the continuity tests I did. I don't have ready access to an oscilloscope, so I'm not sure how to measure the normalization probe. Is there a way I can check it using the AC setting on a multimeter?

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Wed Jun 10, 2020 4:52 pm

You can measure the DC voltage on the output of each the op amps with a DMM if you insert an unconnected patch cable into the corresponding jack socket to disconnect the normalisation signal.

To trace the normalisation signal, which is a PRBS, you'll need an oscilloscope (essential if you're troubleshooting this type of circuitry)

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Re: DIY Mutable Unsuccessful Builds

Post by soupspoon » Wed Jun 10, 2020 5:05 pm

Model is -0.5V and Morph reads out as -0.58V. All other voltages using the unconnected patch cable and mV scaling result in a negligible or near-zero output. I'll need to find an oscilloscope I can borrow for the normalization signal (fingers crossed!).

(I'm realizing now that the negative voltages might not make total sense, but I'm not sure so I'm not going to flip the signs. I'm also not an expert.)

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Wed Jun 10, 2020 5:13 pm

Model should be 1.65V and Morph 1.66V

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Re: DIY Mutable Unsuccessful Builds

Post by soupspoon » Wed Jun 10, 2020 5:51 pm

cnicht wrote:
Wed Jun 10, 2020 5:13 pm
Model should be 1.65V and Morph 1.66V
I'm not sure where to look, given this information. I'm very sorry for the additional work this might cause. There are no obvious solder bridges and I have reflowed both op-amps. They are oriented properly and given the correct supply voltage. The component values for both paths appear correct (given the labels), so I'm not sure what else I can check. Any ideas? Thanks for all the help so far.

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Re: DIY Mutable Unsuccessful Builds

Post by qmulus » Wed Jun 10, 2020 9:46 pm

I'm running into a couple issues flashing my Antumbra Knit (Plaits) build.

1. IC4 (STM32F373CCT6) gets hot when I power on the unit. This doesn't really happen anywhere else on the board. I've check for bridges and did a little reflow and I can't seem to find anything wrong.

When I did a continuity and voltage check, everything seems to be working.

What might be causing this?

2. On previous builds, I used the ST-LINK V2. For my Plaits, Stages and Tides 2 builds, I got a Disco board (STM32F0DISCOVERY) for flashing through the 4 prong connection. So far, it hasn't worked.

Is there a different procedure for flashing with a Disco board?

Below: attempted falsh results

I haven't been able to find any info on how to flash the the board with the Disco

vagrant@vagrant-ubuntu-trusty-64:/vagrant/eurorack-modules$ make -f plaits/makefile upload
openocd -s /opt/local/share/openocd/scripts/ -f interface/stlink-v2.cfg -f target/stm32f3x.cfg -c "init" -c "halt" -c "sleep 200" \
-c "flash erase_address 0x08000000 32768" \
-c "reset halt" \
-c "flash write_image erase build/plaits/plaits_bootloader_combo.bin 0x08000000" \
-c "verify_image build/plaits/plaits_bootloader_combo.bin 0x08000000" \
-c "sleep 200" -c "reset run" -c "shutdown"
Open On-Chip Debugger 0.9.0 (2020-04-17-01:54)
Licensed under GNU GPL v2
For bug reports, read
http://openocd.org/doc/doxygen/bugs.html
Info : auto-selecting first available session transport "hla_swd". To override use 'transport select <transport>'.
adapter speed: 1000 kHz
adapter_nsrst_delay: 100
Info : The selected transport took over low-level target control. The results might differ compared to plain JTAG/SWD
none separate
Info : Unable to match requested speed 1000 kHz, using 950 kHz
Info : Unable to match requested speed 1000 kHz, using 950 kHz
Info : clock speed 950 kHz
Info : STLINK v2 JTAG v25 API v2 SWIM v0 VID 0x0483 PID 0x3748
Info : using stlink api v2
Info : Target voltage: 2.907143
Error: init mode failed (unable to connect to the target)
in procedure 'init'
in procedure 'ocd_bouncer'

make: *** [upload_combo_jtag_erase_first] Error 1
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Re: DIY Mutable Unsuccessful Builds

Post by bawbag » Wed Jun 10, 2020 9:51 pm

Why not continue with the ST-Link?
It needs to be wired as follows:
Image

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Re: DIY Mutable Unsuccessful Builds

Post by qmulus » Thu Jun 11, 2020 1:06 am

bawbag wrote:
Wed Jun 10, 2020 9:51 pm
Why not continue with the ST-Link?
It needs to be wired as follows:
Image
I gave that a go. I saw a difference in the "target voltage". Now it's at 3.2v vs the 2.9v that I was getting before.
It still failed to connect and the STM32 is still getting hot.

I'll reflow it one more time and see if that makes a difference.

_________________________________________________________

vagrant@vagrant-ubuntu-trusty-64:/vagrant/eurorack-modules$ make -f plaits/makefile upload_combo_jtag
openocd -s /opt/local/share/openocd/scripts/ -f interface/stlink-v2.cfg -f target/stm32f3x.cfg -c "init" -c "halt" -c "sleep 200" \
-f stmlib/programming/jtag/erase_f37x.cfg \
-c "flash write_image erase build/plaits/plaits_bootloader_combo.bin 0x08000000" \
-c "verify_image build/plaits/plaits_bootloader_combo.bin 0x08000000" \
-c "sleep 200" -c "reset run" -c "shutdown"
Open On-Chip Debugger 0.9.0 (2020-04-17-01:54)
Licensed under GNU GPL v2
For bug reports, read
http://openocd.org/doc/doxygen/bugs.html
Info : auto-selecting first available session transport "hla_swd". To override use 'transport select <transport>'.
adapter speed: 1000 kHz
adapter_nsrst_delay: 100
Info : The selected transport took over low-level target control. The results might differ compared to plain JTAG/SWD
none separate
Info : Unable to match requested speed 1000 kHz, using 950 kHz
Info : Unable to match requested speed 1000 kHz, using 950 kHz
Info : clock speed 950 kHz
Info : STLINK v2 JTAG v29 API v2 SWIM v7 VID 0x0483 PID 0x3748
Info : using stlink api v2
Info : Target voltage: 3.206856
Error: init mode failed (unable to connect to the target)
in procedure 'init'
in procedure 'ocd_bouncer'

make: *** [upload_combo_jtag] Error 1
vagrant@vagrant-ubuntu-trusty-64:/vagrant/eurorack-modules$

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Thu Jun 11, 2020 2:13 am

soupspoon wrote:
Wed Jun 10, 2020 5:51 pm
cnicht wrote:
Wed Jun 10, 2020 5:13 pm
Model should be 1.65V and Morph 1.66V
I'm not sure where to look, given this information. I'm very sorry for the additional work this might cause. There are no obvious solder bridges and I have reflowed both op-amps. They are oriented properly and given the correct supply voltage. The component values for both paths appear correct (given the labels), so I'm not sure what else I can check. Any ideas? Thanks for all the help so far.
I would do some signal tracing with an oscilloscope

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Re: DIY Mutable Unsuccessful Builds

Post by qmulus » Thu Jun 11, 2020 3:22 am

So I snapped an IR photo of the brain board on my Knit build. It shows that both IC3 (LDO regulator) and IC4 (STM32) are getting really hot.

Upon rechecking for continuity, I found that one of the pads on the LDO regulator (2@1) beeps my multimeter when connected to GND.

Is this normal?
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Thu Jun 11, 2020 3:57 am

Yes

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Re: DIY Mutable Unsuccessful Builds

Post by soupspoon » Thu Jun 11, 2020 9:44 am

cnicht wrote:
Thu Jun 11, 2020 2:13 am
I would do some signal tracing with an oscilloscope
Alright, I have verified the presence of the normalization signal with an oscilloscope. It matches the expected output that has been posted on here before (square wave with somewhat irregular pulse widths). Is there a chance the DAC is just fried? Otherwise, I'll go about checking the signals for the op-amp outputs.

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Re: DIY Mutable Unsuccessful Builds

Post by funketek » Thu Jun 11, 2020 10:10 am

Jtag de-soldering was a success! I used hot air until it just fell out and then spent about an hour with lots of flux and copper braid to get the solder out of the tiny jtag holes. Broke the tip on my soldering iron on the last one, but managed not to lift any pads on the pcb. Flashed the firmware with no problem after it was installed on the correct side. Thanks again forestcaver!

I should probably stop drinking and soldering, but that's not going to happen.. :guinness:

Image


funketek wrote:
Wed Jun 10, 2020 2:40 pm
whew..

Kind of an embarrassing mistake, but thank you for being gentle!

Looking forward to de-soldering the jtag. :doh:
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Thu Jun 11, 2020 10:17 am

Congratulations on overcoming the surface tension!

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Thu Jun 11, 2020 10:21 am

soupspoon wrote:
Thu Jun 11, 2020 9:44 am
cnicht wrote:
Thu Jun 11, 2020 2:13 am
I would do some signal tracing with an oscilloscope
Alright, I have verified the presence of the normalization signal with an oscilloscope. It matches the expected output that has been posted on here before (square wave with somewhat irregular pulse widths). Is there a chance the DAC is just fried? Otherwise, I'll go about checking the signals for the op-amp outputs.
It's unlikely that the DAC is faulty unless you've shorted pins.

Do the measurements on the op amp outputs.

I had unexpected output from design when I didn't solder an op amp correctly. This was verified by measuring their outputs with no normalisation signal present.

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Re: DIY Mutable Unsuccessful Builds

Post by soupspoon » Thu Jun 11, 2020 11:25 am

I'm listing them left to right (the IC labels aren't visible):
For the first MCP6004, the normalization signal is present at two of the outputs. For the second MCP6004, only OUTA has the normalization signal present. The output on the TL072 is a 60Hz, 1.5V amplitude sine wave.

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Thu Jun 11, 2020 11:41 am

You should be able to find the number of the ICs either from the PCB design package into which you can load the Eagle design files, or from the components which closely surround them.

Given the signal you're seeing on the output of the TL072 it would seem that its input is floating. Do you have 60Hz mains where you are?

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