MCP23017 IO Expansion Board Compatible with Raspberry Pi/Micro:bit/Arduino/STM32. I2C Interface Control, 2 Signal Pins Increase to 16 Input/Output Pins, Supports UP to 8 Simultaneous Uses.

The 23017 is a great little chip that allows you to add two 8 bit i/o ports to any microcontroller with I2C. This means that with only 4 wires (SDA/SCL and the 3V/GND power lines) you can have 16 individually programmable digital inputs or outputs that can be connected to switches or to relays, LEDs etc. This CQRobot board has two rows of header pins for the A and B 8-bit ports, also exposing Vcc and GND, so it's easy to wire up to other devices using Dupont leads. There is a red LED that shows when 3V power is on. The board also has an extension header that would allow you to add other I2C devices on to co-exist with the 23017.I connected mine up to a Raspberry Pi Zero W, and using the AdafruitMCP230xx Library for Python was able to set pins up to be inputs and outputs and connect a LED and a switch, for example, input: pin0 = mcp.get_pin(0) pin0.direction = digitalio.Direction.INPUT print( pin0.value )or output: pin1 = mcp.get_pin(1) pin1.direction = digitalio.Direction.OUTPUT pin1.value = TrueThe microcontroller interface of the CQRobot board has six colour-coded silicon wires to connect to your Rasp Pi / Arduino etc, exposing the I2C bus, power and also interrupt lines for the A and B ports. The board design itself is a bit reminiscent of the Pi itself, with four mounting holes in the PCB and the same width as the Pi Zero (the length is about 2/3 that of the Zero).This is a great expansion board and easy to get working.

This product comes in a plastic case and all ready to go with all pins soldered up.It's a time saver in terms of hooking up multiple...ie lots of i2c devices to one controller, and uses a lot less pins than the normal way of just assigning different ports.You can change the i2c address if you want to by getting the soldering iron out and shorting tiny pins, but best if you don't have to as this is a bit of hassle.You can use existing libraries to interface with this but bear in mind you're going to have to have a basic understanding of arduino and i2c.

This is really easy to assemble and I'm not the most nimble of people. Works really well, can't fault it

As with every CQRobot product I have tried, this is a great little board. The quality is excellent, as always, with all the pins pre-soldered, a long connector cable with soft rubber sleeves, and every pin clearly labeled. The board works great and provides 16 additional GPIO pins for whatever microcontroller you're using. I have a number of loose MCP23017 chips, but having a pre-built board like this is so much more convenient and saves a lot of work and messy wiring. My only criticism, and it is very minor indeed, is that it would be nice if the pins extended below the board a few mm so that I could easily drop it onto a breadboard.CQRobot really do go above and beyond to ensure their customers are satisfied and their products stand out from the competition.Note: This is an Amazon Vine review. I was sent this product free of charge in exchange for an honest and unbiased review.

The concept is simple, 5V/3.3V power connection, Ground and a 2 pin I2C as the SCA and SCL signals and the other 2 pins and interrupt A and B lines.. with a connection in and out you can daisy chain up to 8 of these together and create a whopping 128 pins of IO - all you have to do is in 3-bit binary short the address onto the A0, A1 and A2 jumper link positions on the PCB (immediately next to the inlet connector) with all open circuit A0, A1 and A2 are all floating high hence the address of the expansion board is 0x27 - so with all three shorted it is 0x20 address, 0x21 is A0 open others shorted - key information you need to ensure you set this up correctly. This is a fantastic littke board and is very well made. Example software code is on the wiki page. Happy to highly recommend, Andrew

This item came well packed and build quality looks good.All inputs and outputs clearly marked on board as are the address pads.Unfortunately there was little to no information supplied with product, just a couple of references to webpages on packet label.A basic specification sheet was found after a search on the CQRobot webpage, as well as a link to a wiki page containing examples for use with both an Arduino and a Raspberry Pi.I cannot comment on Raspberry Pi example as I have never used one, but the example for the Arduino was extremely complicated and not very well explained (Poor English).The one code example given tried to incorporate everything the MPC23017 could do in one hit and for the average hobbyist (which is what Arduino's are aimed at) this was very difficult to understand.It would be more beneficial to have had simple separate examples of;Simply pulsing a pin on and offSimply reading a pins inputThen a full example of the more complicated interrupt routine, for those that wanted that feature.In summary, Good build but I do think it is a bit expensive, it does what it is made for but it is basically an MPC23017 chip mounted on a PCB.

I have updated the review now that I have found the product wiki and all of the support code for Arduino. This is a board for expanding the amount of IOs that you can use on your Arduino or Raspberry Pi. It is compact. well made and easy to attach. The problems come in programming the functions for Arduino the support is excellent - I have not used it with a Raspberry Pi and so I cannot comment on that aspect. It isn't cheap but this reflects its compactness as most other expansion boards/shields are almost the same size as the Arduino board itself. This is idea if you need to build a compact piece of hardware but it comes at a price.

I have a Micro: bi the Expansion Board is a great bit of kit to include into my latest projects.

Purchased this to expand the number of GPIO pins in Pi. Works just as described.

Die Produktverpackung besteht aus einer Kunststoffbox, die man nach dem Aufbau auch als Aufbewahrungsbox nutzen kann. Die Pins werden durch ein Stück Schaumstoff geschützt, so sollte eigentlich alles gut gesichert sein.Eine Anleitung liegt nicht dabei, dafür ist alles auf der Wiki Seite vom Hersteller zu finden, auch ein Demo Code.Das MCP23017 IO Expansion Board erweitert 2 Signalpins zu 16 I/O-Pins auf Basis des I2C-Busses, bis zu 8 MCP23017 IO Expansion Board können gleichzeitig verwendet werden, so dass bis zu 128 I/O-Pins zur Verfügung stehen, es ist sowohl mit 3,3V als auch mit 5V Pegeln kompatibel.Beispielcodes und die Anleitung für den Raspberry Pi und Arduino Uno befinden sich auf der Wiki Seite.Die Boardmaße ohne Kabel sind ca.: 45mm (L) x 32mm (B) x 11,6mm (H).Die Kabellänge beträgt ca. 21cm.Damit kann man verschiedene Projekte realisieren, z.B. eine binäre Uhr bauen oder mehrere Relais ansteuern, da man mehrere Ports zur Verfügung hat.Preis Leistung von ca. 12€ ist für diese Erweiterung noch in Ordnung, es gibt ähnliche im Ausland auch noch günstiger, dafür muss man länger auf die Ware warten.Von den Funktionen her ist soweit alles in Ordnung, ein paar Tests auf dem Arduino liefen auch problemlos. Soweit bin ich ganz zufrieden mit dem E/A Erweiterungsboard.

The media could not be loaded. Una potente forma de ampliar los puertos de entrada/salida de nuestra Raspberry o Arduino con 16 potros mas, ademas podemos ir acoplando mas tarjetas como esta hasta llegar a tener 8 conéctalas entre si, disponiendo en tal caso de un máximo de 128 puertosComo tengo a mi sobrino estudiando informática, esta tarjeta le ha venido muy bien para practicar.Se basa en el chip MCP23017 de Microchip, tanto el fabricante de tarjeta como del chip disponen en sus respectivas Web de completa información descargable muy útil para aprender a sacarle provechoAdemas viene en un estuche donde guardarlo protegido cuando no lo usemosUn muy buen producto

Ottimo pakage

Physical quality of the product is quite high. Comes in a plastic container. The container is barely large enough to contain the board and wires. But it does. There's no label on the top of the container which specifies what is inside. Would be nice it were nicely labeled rather than a generic CQRobot box.My testing setup inludes a Windows PC, Arduino Nano, breadboard, and some LEDs, resistors, and wires.No directions came with the product. Mostly expected. however the mentioned Wik says "Comes with development resources and manual." Which I guess means comes with the wiki? Kind-of cyclical, but whatever.The cqrobot.wiki page listed in the product description does contain some example code, but not everything that you need. The code requires MCP23017.h, which is not listed or available. I found some other code on the internet for the MCP23017 chip which helped me quite a bit. I ended up using that instead, and installing the Adafruit MCP23017 library in Arduino IDE.There's no details on the product description or wiki on exactly how to configure the address of the board. The cqrobot wiki sample code does show that it's default "7". Which is not the same as the default "0" from the other sample code I found. I didn't see any details on the cqrobot page explaining what R1, R2, R3, R4, R5, and R6 do. Nor what A0, A1, and A2 do. Using a multimeter I found that resistors 4-6 set address pins to vcc, which matches the address 7. I wish this was a bit better described what was going on here, and how to make the change. I'm guessing a 0 ohm resistor, or solder bridge, on A0-2 will set the address to 0. Would be nice since this is a breakout board if those were jumpers or switches to change the address.I did end up getting the board/chip to work! So that's good right.Product does work on 5 or 3.3v rails.