iainmaoileoin
Posts: 16
Joined: Tue Jul 31, 2012 10:57 pm

first experience with a Rs-Pi 23017-2

Sun Dec 02, 2012 2:58 pm

Off the cuff, as I see it. These are my personal comments and represent my opinion

pridopia "Raspberry Pi Rs-Pi I2C 23017 x2 32 bit GPIO Board"

I bought one of these boards off ebay. Quite pricy at £25ish . Probably cheaper to blow a pi than to buy 1 of these ;-)
Anyway. It does what it says on the tin. 4 ports of 8 bits accessable from the pi.
Ports (or bits) can be set to be in or out under software control.
The "manual" that came with the unit was 1 page of pretty poor double sided A4 b/w paper.
Dont actually expect it to help you unless you know what you are doing. It starts "If you already install I2C driver , then". And if you have not? They did show you how to get a python module

I am a C programmer not python, so I had to find and download some 23017 drivers.
My kernel is raspberrypi 3.2.27+ so it has i2c support (all be it disabled in the modprobe start up files)
vi /etc/modprobe.d/raspi-blacklist.conf
vi /etc/modules
Anyway changed those files picked up the i2c tools (apt-get install i2c-tools)
Something not right on my config and I have to do "modprobe i2c-dev" each reboot until I figure out what is not probing.
Then I got some c source code for userspace drivers
wget http://www.open.com.au/mikem/bcm2835/bc ... .13.tar.gz
nice drivers, did what it says on the tin -fits in well with the pridopia board.

I also downloaded the code from http://alanbarr.github.com/RaspberryPi-GPIO/index.html
That too does what it says on the tin (but I could not find a wrapped up package and had to
cut copy paste about 5 wee files). However all compiled up and ran A OK.

Summary.
Not cheap, manual short of advice, web page reference to nathan.chantrell.net - nice page but a lot of digging needed. A package this price should have a nice dedicated web-page to make it easy to set up.

I would recommend the board to anyone needing to breakout more than the RaPi will do and/or
who needs 5v i/o.



The pridopia board has one flaw. There is no easy access to an earth pin on the board.
The 4 x 8 pin connectors that can be set up to do in or our are delivered on a 8 way 0.1 pitch connector. Great but if you are using the 2 x 13 header for other things finding an earth is not easy. Ditto if you are looking for a +5 to handle some pullups.

ghans
Posts: 7882
Joined: Mon Dec 12, 2011 8:30 pm
Location: Germany

Re: first experience with a Rs-Pi 23017-2

Sun Dec 02, 2012 5:11 pm

Are you talking about a expansion board or about the Pi ?
The thread title is confusing.


ghans
• Don't like the board ? Missing features ? Change to the prosilver theme ! You can find it in your settings.
• Don't like to search the forum BEFORE posting 'cos it's useless ? Try googling : yoursearchtermshere site:raspberrypi.org

iainmaoileoin
Posts: 16
Joined: Tue Jul 31, 2012 10:57 pm

Re: first experience with a Rs-Pi 23017-2

Sun Dec 02, 2012 10:06 pm

The talk is about the pridopia expansion board that costs about £25. It has two 23017s connected to the pi I2C. So you have 4 x 8 bit ports that you can address/drive. It does the 3.3/5v buffer stuff too.

Sorry if your confused, was trying to feedback my experience with the add on board.

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