DIY: norns shield

[dan_derks]

sorry to hear about the trouble!

the times this has come up before, it was related to underpowering the rPi. are you using the official rPi power supply? does a different cable / unit help?

a few related posts:

DIY: norns shield

I had this problem the first day and I noticed the red power led on the raspberry Pi started to blink every time it happened. So I searched and found that “In the later models (A+, B+, Pi 2 & Pi 3) the power LED is slightly more intelligent. it is connected to the 5V and will flash if the voltage drops below 4.63V.” I solved this by buying a 3A wallwart and never got these problems again.

DIY: norns shield

Issue resolved, turns out it was the cable, now I have 3 2.5-3A power adapters haha

[Nu_Gravity]

I’ve heard about power noise, but that’s not the problem I’m talking about

[dan_derks]

for sure, apologies if i misrepresented the solution – the crunchy sound you’re hearing is likely the CPU being underpowered, which would lower its capability (rather than hitting its actual limit). a beefy power supply will help ensure that the CPU receives full juice and should resolve the crunch. you’re correct that a better PSU will also ensure that power noise/whine isn’t a problem, but it has also been known to solve the problem you’re experiencing.

it could also be an SD card issue, if you want to try reflashing your card.
unless you’re also seeing SUPERCOLLIDER FAIL messages, the codec/crystal/hardware is likely fine.

just for the sake of ruling out power issues, what PSU are you currently using and which rPi are you using with your shield?

[Nu_Gravity]

5V 3A - non-native rPi
Powerbank 5V 10.000 mAh

the sound is the same if you critical load the ableton (all DAW)

[dan_derks]

hmm. those specs seem alright. thanks for confirming! i’d say the next best thing is to try re-flashing or a different SD card, but there isn’t much else that could go weird with a kit build.

you can check the CPU load through the norns main menu (SELECT / SYSTEM / SLEEP) by pressing K2 on it. that would confirm if the CPU is spiking. which scripts are you using where this sound is present and what CPU readings are you getting?

[Nu_Gravity]

Pools, GRD, changed cards, periodically during operation, the processor was loaded until 27-31%, and this crunch appeared when I switched between menu items, the indication showed that as if noise was coming at the input, although at that moment it was started GRD.

[dan_derks]

ah, yeah 31% is a bit high for those scripts (and I have admittedly have had the same trouble with GRD in the past). Pools is surprising, though. it might be worth pinging threads for scripts where you’re seeing high CPU readings.

also, sorry, I didn’t mean to gaslight you into “this is a PSU issue” – I just didn’t have all the detail I needed to get nitty gritty (eg. if this was on Awake, it’d def be an under-powering issue), but it sounds like some scripts are actually taxing the Pi.

[andrew]

an R synth i wrote hovers around 25% CPU on my shield and seems to suffer from crackly stuff for this reason

bumping up the voice count in moln might be a decent way to test CPU load effects

[snackary]

Hello! I’m pretty new to the Norns community, and have built my shield just a day or two ago. I’m not super tech savvy but got help with soldering (which I felt went okay), didn’t have any problems writing the SD card, etc., but can’t seem to get the screen to turn on. When I plug it I do get the red “on” light on the bottom right of the device, and hear a sound from the aux output (just one long note), but the screen remains absolutely blank! I can attach pictures if that would be helpful, but am at a bit of a loss, and am wondering if anyone has had experience this before / whether I should troubleshoot anything else before attempting to resolder. (I’ve used a few different power supplies, rewritten the SD card a few times – not sure how to diagnose this one!)

Thank you in advance if you have suggestions, happy to attach pictures if that would help

[corpusjonsey]

Try re-flowing the screen header solder points?

[snackary]

Gave this a shot, still no luck!

[alley_cam]

Pictures would be great!

If you have a multimeter on hand, check the continuity between each header pin on shield and the header pins on the display (while display is installed)

Maybe headers aren’t seated fully? It takes a litle force (gentle though)

Also take a look at the Pi header

[snackary]

Here are some pictures – I’m pretty bummed since when re-flowing the solder on pretty much all of the different solder joints to see if it was a faulty connection, but think i messed up one of the header that connects the shield to the pi board. It looked pretty good before, but now the red light turns off when I connect the shield to the pi board. I did check the headers and they were clicked fully in, but there was still no activity on the screen.

Based on the pictures, do you think this is salvageable? I think I might take this to an electrician, but I’m pretty worried about whether there might be any damage to the board itself, and how much that might cost too since I’m currently unemployed I don’t have access to a multimeter or anything besides my soldering tools – I guess it’s kind of my fault for attempting this as a novice!

If anyone has advice for other ways I might troubleshoot, or how much it might cost to get this fixed or built by a professional (if that is possible), I would love any suggestions. Thanks again for those who have helped!

[snackary]

Here are a few more pictures:

[alley_cam]

So it looks like there are a couple bridges between pins on the Pi header where I have circled in red. This could explain the Pi shutting off when connected.

I would recommend using higher heat on your iron. The solder should flow quickly and easily on contact. Some flux would be a big help with proper heat to get everything flowing. It looks like there are a lot of cold solder joints. I tend to crank the heat up on my iron and work as quickly as I can while still ensuring proper flow.

Having the start up tone before was a great sign that Pi and the Shield were connecting properly (besides display) and that the audio engine was working.

Totally salvageable though!

If you reach your wits end and were able mail it out (and back) I would be more than happy to tune it up for free. DM me if that sounds good.

Cheers

[kyanrinner]

Hi all, I recently purchased a norns shield kit, and when I opened the package there was a tiny piece of the PCB board that had come off, possibly due to the shipping carrier(?). I have reached out to monome, but as I await a response I’m wondering if anyone here can help. This is my first project that requires soldering so I am unfamiliar with how everything works. Is this something that I can fix or solder back on myself, or is it something I will need to get replaced. Any help is much appreciated!

[disc0p]

SMD components, especially at that size are very easy. Just place the resistor back in place and heat one pad, it should snap into place, then do the other side. Orientation doesn’t matter.

[kyanrinner]

Perfect, thanks so much for the response.

[dan_derks]

haven’t checked the inbox today, but if this doesn’t work out let us know and we’ll be happy to ship a new board! sorry for the trouble!!

[andrew]

yea it’s doable - you’ll definitely want tweezers though, and you’ll want to be careful not to bridge solder between that capacitor and other components. solder one side in place w/ tweezers then the next side

that size is easy but that part of the board is a little packed so i’ve had some mild troubles with it