OneWire Support

Hi, just wanted to formalise a request for OneWire support following previous discussions here.


I, too, would like to see 1-wire support on the imp.

I’ve just implemented 1-wire (in C) on an LPC-1788 (also Cortex M3), and to my surprise found that the GPIO’s didn’t allow value-changes as fast as was needed to utilize high-speed 1-wire communication. For my application it wasn’t strictly needed, so I didn’t explore using the UART. Might be needed for the imp, though?

As has been noted, we will have 1-wire support at some point. We’ve got plans for a way to implement arbitrary bit-banged I/O without needing any software gymnastics to achieve it.

Sounds good, Hugo. Looking forward to see it.

Please, I would also like to use a DS18B20 for a temp control application. A TMP36 is just not accurate enough.

Hi Hugo,

Any update on the 1-wire support?

Not yet, no. We have other major features on the card OS side which are ahead of 1-wire, such as runnign with wifi off and shallow wakes (where you can wake, do some work (eg sampling some data and storing it in the nv table, then sleep again without connecting to wifi).

Right now I’d say it’s likely to come in Q1 2013, but it does depend a little on what other features come along. There’s a workaround (use an i2c-1wire bridge chip) though obviously that’s non-ideal.

Hi, I would like to get OneWire support as soon as possible too.

I have an application using the DS18B20 running on an Arduino board and I want to port it to the imp. Also, as said before, the TMP36 is just not accurate enough.

Thank you for the great work.

Not that it helps with onewire, but the TMP112 works really well in our experience, and sits on i2c.

Hello Hugo!

Any updates on the one-wire?

Still a way off, sorry. It’s safer to assume it won’t come anytime soon and use an i2c bridge than to wait; we have many many features in the queue and it’s still a long way down the priority list - mainly because no commercial customers are reliant on it.