An easy way to be able to add a Raspberry Pi GPIO Header to your desktop computer or laptop.
About this project
The Raspberry Pi Add-On Market is huge, there’s an add-on board or HAT for almost every electronics project for the Raspberry Pi.
However the only downside this they can only be used with the Raspberry Pi and many Add-ons are incompatible with each other allowing only one to be used at a time.
RTk.GPIO aims to resolve these issues.
The RTk.GPIO is a GPIO Board that is pin-for-pin compatible with a 40-way Raspberry Pi header with compatible software.
We see the Raspberry Pi header layout as a de-facto standard for general input-output experiments, particularly for beginners.
The RTk.GPIO allows you to do the following:
1) Use it standalone – for if you want some general purpose input/output on a normal desktop or laptop computer. Together with our software, this will give you the ability to use Raspberry PI equipment with a standard PC or Mac computer.
2) Use it as an extra GPIO Header – for if you’ve run out of pins on the Raspberry Pi, or want to use two add-on board together. You will gain an extra Raspberry Pi header that is pin-for-pin compatible. You can even use a longer Micro USB cable to make an extension to be able to have your GPIO pins away from the pi.
Along with this the RTk.GPIO Adapter is compatible with a majority Raspberry Pi Addons! You can check out the compatibility spreadsheet to see which ones.
Add-on not listed? Email it to us at email@example.com and we’ll check for compatibility and update our spreadsheet.
.Here at Ryanteck we work with a few schools on using Raspberry Pi in the classroom. Along with this and the introduction of micro:bits teachers are struggling to get funding for their Raspberry Pi Clubs to get add-ons, Micro:bit add-ons and all of the usual funding!
By designing this it allows schools to get a board that allows them to program it on the normal computers in the classroom for non Raspberry Pi Lessons and then move to Raspberry Pi for clubs. Best of all they can justify buying add-ons for their Raspberry Pi clubs instead of limiting them just to be used in those lessons.
Along with this a lot of people’s projects are usually developed on another computer. This allows you to experiment and prototype projects on your normal computer and then move over to the Raspberry Pi later on.
Finally not everyone is able to use a Pi at home because it may cost too much for them to get all of the accessories required to make it work on their monitors at home. This allows people with old computers or laptops to be able to take advantage of the great Pi ecosystem and continue on it when they have access to a Raspberry Pi.
The process of how the RTk.GPIO works is quite simple and works to the end user almost identically as the GPIO pins on the Raspberry Pi.
The first level is your program that you’ve written. Like the Raspberry Pi you use a library to control the GPIO Pins. For you its as simple as using our library instead.
The library then interprets your commands in the same way the Raspberry Pi library does and then transmits it over USB to the RTk.GPIO Board
The RTk.GPIO Board
Finally the RTk.GPIO board receives the message of what to do from the library and then either acts on it (Turning a GPIO On or off) or transmits information back (Such as a pin state) to the computer.
Currently the only planned library is Python which will be compatible with most programs written using RPi.GPIO. We also plan to have limited GPIO Zero support & possibly Scratch GPIO.
This project is a LOT of work in both hardware and software.
We have the first hardware prototype ready to go along with basic software for it. For the finished product we want to refine the hardware more and produce better functioning software.
Finally to get the great price that we’re selling it to you at we need to order LOTS of boards.
The money we fund-raise will help fund the following:
- Prototyping & development Costs
- Hardware costs for production batch.
- Programming & Testing the production boards.
- Software costs for basic GPIO Support
- Kickstarter & Credit Card Processor Fees
- Postage & Packaging Costs
The RTk.GPIO is a device we’ve designed in-house based around an ST Microelectronics MCU which features an ARM Cortex-M0
Running at a fast 48Mhz clock speed with 8KB of Ram at 32 Bit instruction set the heart of the RTk.GPIO is 3X Faster and has 4X More RAM than than a Arduino Uno. We’re finalizing the IC used but it will be either the STM32F030XX Family or the STM32F070XX Family.
This connects to your computer via a USB to UART IC of which we’ve tested the drivers for this IC install via Windows Update on 7, 8 & 10. Pre-installed on the linux distributions we tested and worked under Mac OSX
The MCU itself also supports 5V input on some pins making it ideal for some projects which you may wish to develop with this board instead of directly onto your Raspberry Pi.
As with anything products can be faulty and sometimes cause issues with the most common in electronics being overheating.
We’ve designed the RTk.GPIO board to use RoHS Compliant parts and along with this we have tested all of the parts and try our best to ensure that the product is safe for people to use.
Along with this the design of the board includes components that help protect against short circuitry and followed common design practise to help spread the heat generated across the whole board to keep it cool.
All of the code that the STM32F0X0 IC runs is open source and available on Github at <Insert Link Here>.
We’ve open sourced the code from the beginning as it allows you to give us feedback and if you fancy program in features you want!
The tools required to program the board are of a similar cost so you can program them yourself. We’ll also be offering a service where for a small fee we can update the software on your board for you (after the production of the KS).
How does this compare to alternative boards?
Arduino – Programmable via PC, Genuino – £16-20 , Chinese counterfeit £8-10. Depending on model can require extra drivers which are not fully compatible with all versions of windows.
Raspberry Pi Zero – Requires setup via PC. – Approx £10 Inc SD Card & Header. Not directly programmed via a PC. Sometimes requires extra drivers.
BBC Micro:Bit – Currently only available to students in the United Kingdom. Limited to BBC applications only.
While before we haven’t planned in advance stretch goals for this project they can make a big difference in the features it supports.
- Stretch Goal 1 £9500- I2C Support – The extra cost and work to get this to happen is quite high hence requiring the stretch goal. However if we can support I2C it will mean the RTk.GPIO board will be able to be used with more Add-ons (Those marked in the I2C Column on the spreadsheet).
- Stretch Goal 2 £10750 – AnyIOZero. – We’ll port most of gpiozero to be compatible with the RTk.GPIO Board!
More stretch goals to be added once we reach these!
Risks and challenges
This is not our first crowdfunding project: we have run several on both Kickstarter and IndieGoGo. All of our crowdfunding projects have been completed and shipped on time.
Our dates reflect estimated delivery based on stretch goals being hit.
We have used the factory who are producing the PCB’s and assembling the boards for three of our other products and have found the quality of production is very high.
Along with this we are working to ensure that the components used on the board are genuine ST Microelectronics integrated circuits. This helps reduce the risk of any issues.
For the final product we have changed the USB UART IC We’re using another IC instead of the FTDI one for a few reasons. This also helps prevent against bricking.
The stretch goals have not been tested and may not be able to get completed due to the programming necessary and hardware limitations however the hardware we have selected has a lower risk of this happening.
Finally we will be ordering a prototype batch of the final product to ensure everything works as it should and sending these out to testers before shipping. With this we will also be testing and programming all of the boards before shipping in house to make sure that they all work how they should.