This kit provides all the parts needed to build a Guzunty programmable I/O expansion board for a Raspberry Pi computer. Note that this is a set of unassembled parts - assembly and soldering are required to build the working board. Assembly is not difficult and requires only basic soldering tools (no "surface mount" components are used in this kit, so soldering is easy). Online assembly, soldering, and testing instructions are provided at the bottom of this listing. Here is a photo of the assembled kit:



This kit is identical to that offered on the Guzunty site, but for US customers will cost less with much shorter shipping times.

A Raspberry Pi computer is not included in this listing.

There are many reasons to use a Guzunty expansion board with your Raspberry Pi computer:

1. Protect the delicate GPIO pins of the Raspberry Pi computer
2. Provide up to 30 additional input/output lines
3. Offload the Raspberry Pi CPU for complex I/O tasks
4. Learn about programmable logic
5. Build fun and amazing hardware projects
   

Unlike the GPIO pins of the Raspberry Pi, the Guzunty I/O pins can be used with both 3.3V and 5V external devices. This makes interfacing with other digital electronics easy and with no risk of damage to the Raspberry Pi. The Guzunty increases the number of total available I/O pins by up to 30. This opens up many more possible uses for your Raspberry Pi.

Programmable

Aside from adding up to 30 I/O lines, the Guzunty includes a CPLD (Complex Programmable Logic Device). This allows Guzunty to perform complex logic operations which would otherwise require large amounts of external hardware ("glue logic"), or burden the Raspberry Pi CPU by implementing that logic in software. Complex logic operations can be offloaded to the Guzunty and can run thousands of times faster than equivalent software programs. This is particularly useful for external hardware that requires frequent repetitive operations (like refreshing an LCD display).

The Guzunty CPLD can be reprogrammed any number of times for different projects. The Raspberry Pi itself (and freely downloaded software) is all you need to get started in the world of programmable logic.

The Guzunty project was featured in MagPi magazine, issue #14 page 14.

References:
General information on Guzunty
Assembly instructions
Example projects
General information on Raspberry Pi