I2C communication

[alband]

Hello all,
I've searched I2C but it didn't give any threads; so I'm going to start one.
Can a PICAXE communicate using I2C interface in any way?
Thanks,
David

 

[eclectic]

David.

I've just used Advanced Search for I2C

 

[jsch2603]

I2C Communication

Yes (unless I misunderstand the question), perhaps a good place to start would be with the following:
http://www.rev-ed.co.uk/docs/axe110_i2c.pdf
http://www.rev-ed.co.uk/docs/picaxe_manual2.pdf (see i2c... and hi2c... command sets)
I'm new to I2C, so perhaps others can chime-in with further info.
cheers

 

[hippy]

Search needs to be tweaked for short words like I2C - tag a star on the end; I2C* then add other words to narrow the search down as required.

All PICAXE's can do I2C. This is built-in for the larger chips and can be bit-banged for the smaller ones ( 08 to 20M ). Far easier to use those which support the I2CREAD/I2CWRITE commands.

The 28X1 and 40X1 can also be I2C Slave devices so can be controlled or accessed via I2C from others. All the rest can only control / access I2C devices, not be I2C devices themselves.

 

[alband]

I need small, really, really small. I'm thinking of going PIC as apposed to AXE so I can get a nice small 08M.
How do you "Bit-Badge" a smaller chip to communicate?

 

[womai]

I believe Hippy at some time posted I2C bit-banged code that could be used on a 08M. I also remember reading an apps note for the Basic Stamp which describes bit-banged I2C in detail, and which could easily be ported to the Picaxe. The problem is that once you have that code there isn't much program memory left for anything else.

If size is a concern, maybe a surface-mount 18X would fit the bill? It has native I2C and at the same time offers much more program memory. The SMT version is a SOIC package which actually isn't that difficult to solder, but doesn't take much more space than a DIP packaged 08M.

Wolfgang

 

[alband]

I need SMT 08M style small.
I'll look for hippy's document.
Search "I2C* Bit-Badge"?

 

[westaust55]

That's "Bit Bang" not "bit Badge"

 

[womai]

Here are the links to the BS I2C bit-bang routines + I2C description:

Code:

http://www.nutsvolts.com/media-files/511/stamp1104code.zip

Articles:

http://www.parallax.com/Portals/0/Downloads/docs/cols/nv/vol3/col/nv85.pdf

http://www.parallax.com/Portals/0/Downloads/docs/cols/nv/vol3/col/nv79.pdf

Webboard I2C discussion:

http://forums.parallax.com/forums/default.aspx?f=5&m=2373

Some hints for debugging an I2C bus:

http://www.parallax.com/Portals/0/Downloads/docs/article/i2cSystemswithHPScope.pdf

Good luck with the conversion to the Picaxe 08M! Hope Rev-Ed does not mind links to the site of "it shall not be named" - but given the size & excessive price of that Picaxe alternative chances you'll go for it are probably zero anyway. (it's MUCH bigger than an SMT Picaxe 18X)

Wolfgang

 

[alband]

Hmm,
Thanks.
I'm trying to select some chips for a wireless project with size in mind. I know know that PICAXE can support I2C with different levels of difficulty, would it work with UART or any other serial protocols?
Thanks,
David

 

[ciseco]

they do an 08M smt dont they? i've got smt 14m's ?0.20 more and they are small, what I would like is the smaler SS version of PIC that powers the 28x1, thats a similar size as the 14m smt but very difficult to solder without the right kit.

How small a board do you need?

Miles
________
Mercedes-Benz R171 picture

 

[alband]

Put it this way if 1mm x 1mm is possible, I want 1mm x 1mm