ATtiny85 with i2c

Other Hardware 3rd Party Boards
1

Hi All,

I've been through all the posts relating to this issue (on google as well).

Basically with all the debugging issues I'm having with ATTiny boards I want to connect an LCD to the board. I've downloaded the LCD i2c library that has been tweaked for the ATTiny85.

I basically get the LCD to light up, and then it flashes everytime the loop function occurs (although there is no way for me to know if it is exactly in line with the loop). Anyway - it appears as if the i2c connection is partially working.

I've also used the Tinywire library....

There is simply too many different bits of code to post up here, so my first question is. Have people on this forum had success with this - and if so are they able to point me to the libraries they used?

The other question I have is around debugging the boards - are there any other (easy) mehtods to debug these boards without relying on an LED (I need more info than a light turning on and off).

Cheers.

2

(deleted)

3

AFAIK this one should work:

GitHub - SpenceKonde/TinyWireM: I2C library for USI-using chips with support for 1634 added - code ripped off from Adafruit, who in turn took it from BroHogan's code on Arduino Playground (I think I used it with GitHub - SpenceKonde/LiquidCrystal_I2C_Tiny: Library for the LiquidCrystal LCD display connected to an Arduino board. successfully for a 2004 display)

If it doesn't let me know, because it's the one I was planning on integrating into my core per Consider "improved" versions of standard libraries (I2C, SPI) · Issue #53 · SpenceKonde/ATTinyCore · GitHub

4

Thanks for the help guys. I've purchased a logic analizer so will be interested to see how that goes.

@DrAzzy the I2C library I found was a different one so that is a good start. I'm using 1602 displays but figure they should still work.

If it doesn't work I will let you know. Just FYI - I'll be using it with another I2C sensor IC (both sharing the i2c ports). I know it works because people have done it before without any issue.....

5

@DrAzzy

I've downloaded the libraries you've mentioned above. You might be able to clarify things for me.

When I verify the code (github example) an error comes up that has something to do with selection of appropriate wire/tinywire library.

C:\Program Files (x86)\Arduino\libraries\LiquidCrystal_I2C_Tiny-master/LiquidCrystal_I2C_Tiny.h:16:27: fatal error: SoftI2CMaster.h: No such file or directory

There is some sort of #ifdef series of statements in the LiquidCrystal_I2C_Tiny.h file which is not excluding the wire.h and SoftI2C...h file. I'll try and manually delete everything to do with the wire.h ans SoftI2C.... and try that but just letting you know it doesn't work as is. (or if it does, there are some comments/instructions missing....)

UPDATE.... This is the first set of libraries that I've been able to get working with the ATtiny so thanks a lot. Not sure why the declarations are playing up as they all look ok although I've had issues with the Arduino IDE playing up with them before.

Cheers