we just dm’d but i’ll ask here to confirm

if i have crow, w/, and jf on a bus network together i guess i need to always keep pullups on the crow high…true/false?

do i also need a powered board for the bus? or does eurorack power supplied to crow have enough juice for the connected modules ii needs?

edit: nevermind…i see you asked basically the same thing in the other crow specific thread

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Oof, I guess it didn’t occur to me what was happening when people were discussing turning Crow Pullups on/off.

Since you’re only supposed to have 1 source of power, it’s scary that turning pullups on on Crow could cause damage with a Txb (or any other bus power solution like busboard jr or TT backpack) providing power to the rest of the modules.

Unless I’m misunderstanding.

UPDATE: NO DAMAGE. STOP WORRYING.

No damage will be caused. the bus just might not be as stable as it could be.

GREAT! Thank you. Sorry for any paranoia or fear mongering I may have caused

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so i wonder, how difficult it would be to make a version of TXb or something similar that would check if rise/fall time is within a good range and indicate it with an LED?

the main reason it’s difficult to give an advice on pullup values is because in setups with so many variables there isn’t some absolute “good” value, especially when you combine multiple pullup resistors. the end goal is to ensure rise/fall time is within a good range (detailed info here). if you have an oscilloscope you could use that to analyze your bus, but if we had an easier way to measure it it could help more people with troubleshooting and deciding on which pullups should be enabled and whether an additional busboard is needed.

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quick question
is there a way to connect crow/teletype/justfriends/txi nad have crow talk to JF directly? teletype is going to be master?

Damn, the problem returned… TT read faderbank values correctly and was running fine…
The next day TT froze again… I was wondering what others diy-ed to connect the faderbank jack to the i2c bus… Something is wrong with the chassis I’ve used or should I be looking for problems on the faderbank pcb?

hi everyone. anyone using ER301, Just Friends, Teletype, Ansible and 16n faderbank on the same i2c bus without a dedicated i2c powered busboard? TT as master.

thanks! :slight_smile:

Yes, you can have either crow or Teletype talk to Just Friends and TXi. On crow try ii.jf.help() or ii.txi.help() to see available commands. With all of these modules wired together you can send commands either from crow or from Teletype, though using both at once is likely to cause issues possibly including module crashes. In particular crow will now print a warning if I2C lines are in use and crow didn’t initiate communication.

You can check out all the schematics and board files for bpcmusic’s TXb, seems very straightforward. Any kind of disturbance in the I2C bus definitely has the possibility to freeze Teletype, but if you think it is a very intermittent problem you might want to try the most recent beta firmware for Ansible and Teletype here, which includes a patch that limits the number of retries Teletype will do for I2C operations.

I think probably this is doable with newer Teletypes (black PCB), I’ve used a similar number of devices (though not 16n) with no trouble.

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This link is broken
Thanks

found it, will add redirect tomorrow: https://monome.org/docs/modular/iiheader

sorry that these older docs still haven’t been thoroughly vetted — please email all broken links to help@monome.org :revolving_hearts:

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Thanks Dan!

I found the broken link looking for info on whether I could usefully connect Crow to Ansible and W/ in addition to it already being usefully connected to JF.

I went ahead and connected them all anyway but never really found the right documentation. Weird…

Also, it seems that the Users Guide to i2c could benefit from adding a bit more detail on Crow…

Thanks!

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Dumb question but I don’t want to order the wrong thing: will these work for i2c?

yes! that’s what i use - i don’t even bother heat-shrinking / taping / gluing the ends together, i just tear off a strand of 3 and attach them and it works perfectly : )

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Yep. I use these and have hooked up Teletype, TXO, TXI, TXN, JustFriends. just strip 3 at a time. I also use a small sharpe mark on 1 side so the GND goes to the GND. Or you can just remember the color of 1 of the strands. I’m just dumb.

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Thanks, I built a txb recently for connecting the faderbank properly. Also connected Ansible TXO TXI Crow JF and ER301 to TXB and powered it from the busboard, TT froze. Just connecting TXB (powered) over i2c to t TT, TT froze and wouldn’t boot. The backpack I built previously seems to work more accordingly and as you stated it’s a pretty straightforward build, what could go wrong (TXB is in fact the backpack). The puzzling thing is that things will work for some time but all of a sudden TT will freeze up and I have to power down. Cables are short and connected as they should be, some are daisy chained. I’ve just updated Ansible and TT to the firmware you pointed out, perhaps this will solve the issue. Should you have other advice considering the above, please let me know.

Hey everybody. So, thanks to finishing my TXo and TXi builds this week, I finally got my rack all built out. This is what I ended up with, choosing to have a TT be my initial sequencer, but also having a crow in there for good measure. Everything laid out looks as so:

I put my i2c ribbon cable together where the first port originates on my (Black PCB) teletype, passing through each of the modules. I was lazy, and didn’t want to do one long ribbon cable, so, i Wired everything as so:

TT; TXi; TXo (this one, I have one set of pins be the final of a daisy chain from the TT and the start of a second daisy chain); crow; teletype; w/

For some reason, it appears as if my TT has some real troupe talking to my JF. Signal begins to falter pretty badly, and often times no signals reach JF at all.

I am curious, with this length ofi2c, would it be best if I had a powered bus board? Was my daisy chain breaking at the TXo the issue and one long ribbon cord would work? Should I love the TXi and TXo to the other side of the TT and have them each going out their own way?

If anybody has some thoughts I’d appreciate it!

This configuration I don’t think should be a problem for a black PCB Teletype, I’ve used this many devices successfully in a larger case. Probably try troubleshooting your connections individually, seeing if you have problems with crow -> JF, etc.

What do you mean by first and second daisy chains? Separate ribbon cables?

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In regards to testing, the crow worked just fine with JF. After I did that, I stopped my crow script (awake on my norns) and the JF script began working… for a few minutes before the signal clearly died out and the JF went quiet.

But yeah, the daisy chain I’m mentioning is two different ribbon cables, one connecting the TT, TXi and TXo. I then have a different cable going TXo, crow, JF, and w/

I’m guessing this would most likely be prevented with one ribbon cable, but wanted to see if this distance was too much for the i2c before going in there and moving all my 6pin connectors to a new single cable.

Hi All,

I have just hooked up some modules with i2c fo the first time. Here is the chain order:

ansible > ansible > crow > w/ > just friends

I have used crow to connect to just friends over i2c with Norns and it works great but I am having trouble getting any results from Polyearthsea running on the Ansible that is next to crow in the chain. I have made sure the pull up resisters are on on the crow. I have a few questions. Thanks.

Does the chain look okay?

Is having two ansibles connected together okay?

Is there a crow command that will make crow list which modules it sees on the i2c chain?