ATtiny85 one wire issue

[orgua]

ATtiny85 one wire issue

[dakarym]

I put a scope on the bus. Here is the OW bus messages, this is just repeating

Message detail of 'shorter' message

Message detail of 'longer' message

[orgua]

oh man, i missed your issue. sorry. were you able to solve your problem?

i can give you some hints for your problems:

• calibrate by bus-timing has the following setup: upload sketch to controller and hook it up to a OW-master. controller will listen to the bus and determine value_ipl by measuring the resetpulse
  • but this won't work with your attiny, because it should have no serial
• you are right, the "attiny85-4slaves.ino" example was broken due to changes in data-types, newest lib-version works now

with which attiny-library are you working? arduino itself does not support these chips.
did the compiler tell you, that your value_ipl has to be determined or did you stumble on "calibrate_by_bus_timing" yourself?

[dakarym]

i haven't been back to think for a long while. still something that is interesting to do. i'll have to put the hardware back together and get back to it to try. i'll see maybe this weekend

…

On Sun, Aug 20, 2017 at 6:20 PM, inʒo ***@***.***> wrote: oh man, i missed your issue. sorry. were you able to solve your problem? i can give you some hints for your problems: - calibrate by bus-timing has the following setup: upload sketch to controller and hook it up to a OW-master. controller will listen to the bus and determine value_ipl by measuring the resetpulse - but this won't work with your attiny, because it should have no serial - you are right, the "attiny85-4slaves.ino" example was broken due to changes in data-types, newest lib-version works now with which attiny-library are you working? arduino itself does not support these chips. did the compiler tell you, that your value_ipl has to be determined or did you stumble on "calibrate_by_bus_timing" yourself? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#29 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AZI_YxQe4quOYQBALI6nSU2E6963ZESdks5saFzCgaJpZM4MajXD> .

[mursel]

As I understood I can use OneWireHub to make my attiny85 (in my case) as 1-wire device through emulation. Correct me if im wrong.

UPDATE: Thanks a lot for this lib... it's perfectly working on my attiny85 as slave.

[Giermann]

I'm using this library for almost 3 years now, but a rather old version, slightly patched to work on (my) ATtinys. I was unable to use more recent code on my 1-Wire bus because of the timing. Further I had to run the Tiny85 at 8 MHz, which I'm fine with - but still my clients keep to disappear from the bus, cause read errors - but everything turns good itself on the next reading, so I do not care much about it.

These days I started another approach to emulate a DS18B20 and faced the same problems as @dakarym .
I even tried to run the Tiny85 at 16MHz (PLL), which does a better job - but still the device disappears, gives read errors or simply 0xFF register content. I verified this with a Logic Analyzer, but don't know the source of the problem.
I ran "calibrate_by_bus_timing", which gave me value_ipl=13 at 8 and 16 MHz.
There's no bus issue, as I'm running a DS9490R in a test environment with less than 1m cable.
Everything works as expected on an Arduino Nano (at 8MHz, but not on the Tiny.

I read about the inaccurate clock timing of the Tinys and guess the Nano runs a real oscillator.
Does anybody have experience with this on Tiny85?

@mursel - at what environment does your attiny85 run perfectly?
Internal clock? Which bus master?
Maybe I should switch to my own (Arduino based) bus master to solve the timing issues on my production bus, but what's wrong with these Tinys?

[Lukkoz]

I just tried the newest version of the library with ATtiny85. At first, it was now working at all but after switching from 1 MHz internal oscillator to 16 MHz external one everything works perfectly.