1935

This is maybe a stupid question, and I hope I’m in the right place here.

I’m interested in playing with a Norns Shield, and the site seems to be out of stock so I figure I’ll try the DIY route. Issue is, I have no idea where to start.

I’ve seen I can apparently purchase some parts required on Pusherman here, but I’ll need parts listed on the full BOM here. Is it then a case of going through the list and buying each part from the shopping list column, then learning SMD to put it together?

1936

It looks like it’s Norns Shield is still in stock:

https://market.monome.org

1937

Yeah, I thought so too but trying to buy one says it’s out of stock on the checkout screen. :pensive:

1938

So the Pusherman is a bare PCB so yes you will need to buy the full BOM as posted Octopart. You can try to add all the parts in a column to a shopping cart on Mouser, DigiKey, etc. It is unfortunate that you probably won’t be able to get all of the parts you need from one vendor so be prepared to make a couple (few) orders at different places. Then yeah just solder it up and put it together/program it as instructed on the norns-shield github. You might want to get some sort of case or front/back panel. There’s a thread on that.

1939

I think you can buy completes on reverb.com or maybe set up reminders on ebay, reverb and other buy/sell places?

1940

Greetings all. I’m obviously a bit late in the game here, and struck with the CS4270 dilemma. Looking back it seems chips could be had earlier in the year, but word has obviously spread on the rarity and demand for this chip and current Ali Express prices for genuine are ludicrous.
Just got me thinking, with so many people wanting these, has anyone considered adapting to the CS4271? The package is different being a 28 pin instead of 24, but it appears to be a very similar chip, just a small step up in spec from the CS4270.

Would anyone knowledgeable like to comment of the feasibility of swapping in this chip? Could it be as simple as a reroute to the new package? Or would substantial changes to the codebase also be required?

1941

they appear to have entirely different control register layouts, so i’d expect at least some minor driver changes would be needed. (also new chip has 2x or 3x the power draw, might not be an issue.)

compare table 7 / etc

i have forgotten where the soundcard driver code lives right now. maybe @murray knows.

1942

Here’s monome repo’s cs4270 driver

It looks like there’s spi and i2c support available in an existing driver for the cs4271:

linux/cs4271-i2c.c at norns-4.19.y · monome/linux · GitHub
linux/cs4271.c at norns-4.19.y · monome/linux · GitHub
linux/cs4271.h at norns-4.19.y · monome/linux · GitHub

1 Like
1943

For completeness the device driver for the audio system lives here:

1 Like
1944

heads up that these aren’t even the same pinout/package (4270 is TSSOP24, 4271 is TSSOP28)

in short (to all the DIY people here) don’t expect to switch parts without doing a bunch of engineering (this is an incredibly annoying aspect the hardware industry)

i’m looking at alternative codecs (so we can all continue building norns/shields/etc)… here’s the list of already-supported-in-linux: linux/sound/soc/codecs at master · torvalds/linux · GitHub

if anyone (who has enjoyed these schem/board files) has time to help cross-reference global stock availability (via octopart) and specs/capabilities (stereo in/out, good snr, etc) i’d hugely appreciate it!

7 Likes
1946

I’ve been intending to get a norns around September and have been getting more and more anxious about availability as I’ve seen the ICs get more and more illusive, but this has put that anxiety to rest and reminded me that no matter what happens you good folks at Monome will be doing everything you can to make these accessible to the people, so thank you!!

2 Likes
1947

I have some CPU issues with my shield (based on Pi3, not plus)
Some scripts(like passersby, less concepts, etc) use to much cpu and crunchy sound as result
I use 3A power adapter and some times use diy grid(with grid cpu is more higher)
I change cables, power adapters, reflash firmware, but no results. Any ideas?

1948

Picked up a shield PCB on sale today just in case.

1949

these aren’t even the same pinout/package (4270 is TSSOP24, 4271 is TSSOP28)

…as stated in my post, but as I said, rerouting in Eagle would not be hard and I’m happy to tackle it if that’s all that’s needed.
The only difference I can see that may need ‘engineering’ is that the 4271 has a “Differential Analog Audio Output” with a +/- for each output channel. I must admit I don’t know what that means, maybe for feeding differential amp circuit? Does anyone know, could we just take the +ve lines and ref to GND and leave -ve alone?

On the other hand, changing the driver is not a job I could tackle.

1951

It also says

"The CS4271 automatically uses the on-chip oscillator in the absence of an applied master clock”

The both have the same MCLK input, could we not just feed the CS4271 with the same clock signal as the CS4270?
Sorry, I could be out of my depth here.

1952

Sometimes a different USB cable can help. Here are some notes. Edit: Sorry, didn’t notice you’ve tried different cables already.

1953

Having just assembled my Shield (Monome, not diy) I’ve noticed that my e3 has a very rough/grating travel. It’s not touching the acrylic etc, feels like a bad encoder, performs fine with the interface. Could I have a savvy local tech replace the encoder? Are these hard to come by these days?

Edit: what I mean by ‘works fine with interface’ is that encoder does not exhibit jumpy behaviour within Norns, just the physical encoder grinds within its mechanism.

1954

A post was split to a new topic: norns: midi over ethernet

1955

With the CS4270-CZZ chip being so difficult to obtain lately, I would like to see about creating a norns shield variant that uses a more readily avaliable codec.

I have in mind this one.
The WM8731CLSEFL is a different package (28 pin qfn) of the same chip used on the Fates pcb.

Once the pcb edits were made to use this chip on the norns shield instead of the CS4270, What modifications would be needed in the norns operating system to allow for the use of the new chip?

1956

This very thread starting from this post should give you the details.