wraggster
September 9th, 2014, 21:51
http://hackadaycom.files.wordpress.com/2014/09/pimagic.jpg?w=580&h=321
The Raspberry Pi has been the basis for many cool projects. Even so, Models A and B have been criticized for having only a handful of GPIO pins available. Sure, the new Model B+ (http://hackaday.com/2014/07/13/introducing-the-raspberry-pi-b/) has a 40-pin GPIO header but what if you want to use your old RaspPi with a bunch of in and outputs? [Steve] is one of those guys and has done something about it by creating a pretty neat solution he calls the PiMagic (http://croztech.wordpress.com/pimagic-interface-board-about/). It’s a Pi Plate that has an on board ATMEGA328 running an Arduino bootloader. The RaspPi and the Arduino communicate via UART as [Steve] felt it was a bit simpler than going the SPI or I2C route.
The RaspPi GPIO’s run on 3.3v and the ATMEGA328’s like 5v. To solve this, the PiMagic has a Level Shifter that keeps the I/O of the two boards happy. Older Pi’s had a problem burning out PCB traces when supplying too much current on the 5v supply line. [Steve] threw in a fuse that will burn out before the Pi does to ensure that no Pi’s were harmed in the making of this project.
Now that a bunch of I/O are available, how do you physically access them? Well, the PiMagic has female headers in the typical Arduino layout. This way any Arduino Shield will plug right in. [Steve] made all his source files available (https://github.com/croztech/pimagic) for those who want to make one themselves. Find an assembly video after the break.
http://hackaday.com/2014/09/09/adding-io-to-the-rasberry-pi-models-a-b/
The Raspberry Pi has been the basis for many cool projects. Even so, Models A and B have been criticized for having only a handful of GPIO pins available. Sure, the new Model B+ (http://hackaday.com/2014/07/13/introducing-the-raspberry-pi-b/) has a 40-pin GPIO header but what if you want to use your old RaspPi with a bunch of in and outputs? [Steve] is one of those guys and has done something about it by creating a pretty neat solution he calls the PiMagic (http://croztech.wordpress.com/pimagic-interface-board-about/). It’s a Pi Plate that has an on board ATMEGA328 running an Arduino bootloader. The RaspPi and the Arduino communicate via UART as [Steve] felt it was a bit simpler than going the SPI or I2C route.
The RaspPi GPIO’s run on 3.3v and the ATMEGA328’s like 5v. To solve this, the PiMagic has a Level Shifter that keeps the I/O of the two boards happy. Older Pi’s had a problem burning out PCB traces when supplying too much current on the 5v supply line. [Steve] threw in a fuse that will burn out before the Pi does to ensure that no Pi’s were harmed in the making of this project.
Now that a bunch of I/O are available, how do you physically access them? Well, the PiMagic has female headers in the typical Arduino layout. This way any Arduino Shield will plug right in. [Steve] made all his source files available (https://github.com/croztech/pimagic) for those who want to make one themselves. Find an assembly video after the break.
http://hackaday.com/2014/09/09/adding-io-to-the-rasberry-pi-models-a-b/