Hi Kevin, I was thinking separate packages for different implementations, and then syscfg knobs inside the respective ones. E.g. GPIO/timer and UART selection. These packages would implement the ‘1-wire’ API, and chip drivers would then depend on that API.
The PJRC API is simple, which I like. Seems like a good starting point. > On Jul 3, 2018, at 3:31 PM, Kevin Townsend <ke...@adafruit.com.INVALID> wrote: > > Hi Marko, > > IMHO, The PJRC lib is a sensible basis for a Mynewt 1-Wire package since it's > seen a fair amount of real-world use, and the underlying implementation could > be configured via the syscfg.yml file (timer+GPIO or something else like UART > if you have one free)? > > Kevin > > > On 03/07/18 12:07, marko kiiskila wrote: >> Sounds like a candidate for driver interface, not HAL. I agree with Miguel. >> User could pick the implementation which uses UART, or one which >> uses hal_timer with hal_gpio. >> >> However; Sam, you don’t think a generic driver interface makes sense? >> If you had driver package which implemented an API similar to this: >> One-Wire Library, https://www.pjrc.com/teensy/td_libs_OneWire.html >> <https://www.pjrc.com/teensy/td_libs_OneWire.html>, >> would you have been able to use it? >> >>> On Jul 3, 2018, at 3:11 AM, Sam Lewis <sam.vr.le...@gmail.com> wrote: >>> >>> It might be more difficult to make a generic driver for but I've had some >>> great success using a UART peripheral to read/write 1 wire devices. There's >>> a good writeup of how this works in this app note: >>> https://www.maximintegrated.com/en/app-notes/index.mvp/id/214 >>> >>> The benefit is less CPU time needed for bit banging but you need to make >>> sure your 1 wire device fits the timing constraints of your UART peripheral. >>> >>> Just thought it was worth mentioning, might be something to consider. >>> >>> Sam >>> >>> >>> >>> On Tue., 3 Jul. 2018, 6:11 am Kevin Townsend, <ke...@adafruit.com.invalid> >>> wrote: >>> >>>> Hi Miguel, >>>> >>>> Good to hear! >>>> >>>> Yeah, GPIO is the only way I've ever implemented this and I think a >>>> simple SW implementation is the way to go here. >>>> >>>> K. >>>> >>>> >>>> On 02/07/18 21:39, Miguel Azevedo wrote: >>>>> Hi Kevin, >>>>> I actually do have some code for 1-wire I implemented a few days ago. >>>>> AFAIK most MCUs we support don't have 1-wire specific hardware, so why >>>>> not have a general implementation(using hal_timer) instead of one >>>>> implementation per MCU? >>>>> >>>>> Thanks, >>>>> >>>>> Miguel >>>>> On Mon, Jul 2, 2018 at 8:10 PM Kevin Townsend >>>>> <ke...@adafruit.com.invalid> wrote: >>>>>> Is there any interest is discussing how to add Dallas 1-Wire support to >>>>>> the HAL? https://en.wikipedia.org/wiki/1-Wire >>>>>> >>>>>> It's a bit of a niche item, but an interesting protocol (you can power >>>>>> some devices from the single GPIO line) and there are some very common >>>>>> and cheap waterproof temp sensors and a few other common items that are >>>>>> only available in 1 wire. >>>>>> >>>>>> I'm happy to put one or two test drivers together for common items like >>>>>> the DS18B20 (https://www.adafruit.com/product/381) ... but the HAL >>>>>> implementation is something that should probably be discussed with the >>>>>> wider community first. >>>>>> >>>>>> Kevin >>>>>> >>>> >> >
