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USB to I2C breakout board??

Posted: Mon Jan 20, 2014 11:45 am
by redhawk
I was looking online for the possibility of operating I2C devices via USB and found the following - http://uk.farnell.com/jsp/displayProduc ... N-LISTINGS
According to the datasheet it supports Windows, Mac, Android, Linux 3.0+ and communicates by using virtual com port.
This would be ideal for me since one of my main reasons for using USB anyway was to put an FM radio inside my PC to replace the one I have that's not XP compatible.

Does anyone have experience with such devices or could recommend something cheaper that's XP and Raspbian compatible??

Richard S.

Re: USB to I2C breakout board??

Posted: Mon Jan 20, 2014 4:07 pm
by mikronauts
Why not simply use the Pi's I2C ports?

rev1 Pi's have one I2C port on the 26 pin header

rev2 Pi's have two I2C ports, one on the 26 pin header, one on the P5 header (on the bottom of the board)

I've used the top port with great success, and I even designed a Pi prototyping board so I could use the bottom port :)

(see EZasPi (B) at the link in my sig)

Re: USB to I2C breakout board??

Posted: Mon Jan 20, 2014 4:33 pm
by redhawk
Sorry I should have mentioned this early but I've already done i2c work on the Pi so I'm well aware of this capability.
I want to build a USB device with incorporated i2c device i.e. FM radio with headphone socket or an FM + RDS transmitter etc. the kind of gizmos you rarely find in shops or eBay.
Being USB it would also mean I could use this device on other operating systems or equipment lacking in i2c support like Windows PC, Linux PC or Android TV Box.
While it true there isn't much point doing this on a Pi it could provide a solution for operating 2 i2c devices with the same address line.

Richard S.

Re: USB to I2C breakout board??

Posted: Mon Jan 20, 2014 6:16 pm
by meltwater
Interesting product, I've been looking at similar devices since it would be useful to use the same i2c devices on a normal pc too.
Even connecting to an i2c io expander would be handy.
If you can find out the usb protocol it uses then you'd be able to drive it using python (on both pc and pi).
Unfortunately I think farnell have min order value, but will keep an eye out for them at a decent price.

Re: USB to I2C breakout board??

Posted: Mon Jan 20, 2014 8:09 pm
by mikronauts
Ok, I now better understand what you want to do.

Easiest path: Add a USB-serial converter to the Pi's serial port; plug the USB end into a PC, control the Pi with a simple serial protocol (that would in turn control your tuners)
redhawk wrote:Sorry I should have mentioned this early but I've already done i2c work on the Pi so I'm well aware of this capability.
I want to build a USB device with incorporated i2c device i.e. FM radio with headphone socket or an FM + RDS transmitter etc. the kind of gizmos you rarely find in shops or eBay.
Being USB it would also mean I could use this device on other operating systems or equipment lacking in i2c support like Windows PC, Linux PC or Android TV Box.
While it true there isn't much point doing this on a Pi it could provide a solution for operating 2 i2c devices with the same address line.

Richard S.

Re: USB to I2C breakout board??

Posted: Mon Jan 20, 2014 9:26 pm
by meltwater
mikronauts wrote:Ok, I now better understand what you want to do.

Easiest path: Add a USB-serial converter to the Pi's serial port; plug the USB end into a PC, control the Pi with a simple serial protocol (that would in turn control your tuners)
redhawk wrote:Sorry I should have mentioned this early but I've already done i2c work on the Pi so I'm well aware of this capability.
I want to build a USB device with incorporated i2c device i.e. FM radio with headphone socket or an FM + RDS transmitter etc. the kind of gizmos you rarely find in shops or eBay.
Being USB it would also mean I could use this device on other operating systems or equipment lacking in i2c support like Windows PC, Linux PC or Android TV Box.
While it true there isn't much point doing this on a Pi it could provide a solution for operating 2 i2c devices with the same address line.

Richard S.
The bonus with that approach is that once you have the control working over serial you can replace the cable with a bluetooth serial module. Allowing similar control over a bluetooth serial link.