What is it?

Does your design have a free serial port (UART, I2C, SPI)? If so you can add many more I/O's and control features.

The ABBY-IOX is an I/O Co-Processor module that greatly expands the I/O and functional capability of micro-processor designs such as the Raspberry Pi, ESP32, RP2040, STM32F, and many others. The module is a parallel expansion processor that offers the following features:

• Up to 20 (19 on SPI version) independent GPIO pins that can be configured as inputs or outputs.
• Up to 16 (15 on SPI version) externally edge triggered event inputs.
• Up to 10 PWM servo control outputs.
• Up to 10 digital capture channels (frequency & period measurements).
• Up to 8 (7 on SPI version) rotary encoder inputs.
• Up to 4 hardware event outputs.
• 12 bit fast ADC with up to 10 multiplexed input channels.
• DIY programming supported with the ABBY-IOX-BREAKOUT board.

The ADC interface features automatic background conversions across multiple channels. Oversampling up to 65535 samples with mean average and MIN / MAX readings on all 10 channels.

External edge triggered events can be triggered on the rising, falling, or both signal edges.

The ABBY-IOX also offers built-in support for up to 8 rotary encoders with direction, rolling count, and rotational speed.

Each GPIO can have pull-up or pull-down resistors on both inputs and outputs. Outputs can be push-pull or open-drain with programmable current drive. I/O expansion on the ABBY-IOX module uses one of three serial bus typologies which effectively expands the target processors I/O capability up to a 10:1 factor.

I/O functions can be mixed between all available GPIO pins.

Why did I make it?

In many designs I needed more I/O functionality and sometimes additional features. Even using MPU's such as the ESP32 that feature an ample supply of GPIO's and bus controllers, sometimes it wasn't enough. The ABBY-IOX module allows many more I/O's and features without additional development time or expense. The ABBY-IOX offers a choice of I2C, UART, or SPI serial interface.

What makes it special?

The ABBY-IOX device offers greatly enhanced GPIO expansion and built-in features in a small low cost package. Complete documentation, development library, program examples, schematics, and other information can be found on the Abbykus-IOX Github site. The 32 pin module can be surface mounted on a PCB, mounted via headers, or DIY wired into new or existing designs. It can also be used as a stand-alone micro-controller for many IOT and hobby projects. Development, debugging, and rapid gang programming are supported with the IOX-BREAKOUT board (more info below).

Additional Tools

• A C++ library is available on the GitHub repository for use with Arduino and PlatformIO development environments. The library targets these IDE's but can easily be ported for use in other development platforms (example: Espressif ESP-IDF).
• Also available on Tindie is the ABBY-IOX-BREAKOUT board with connectors available for all serial bus configurations of the IOX module (I2C, UART, and SPI). The breakout board also has a connector for the ST-LINK V2 development dongle from STMicroelectronics. This allows DIY programming of the module using STM32CUBEIDE or platformIO development platforms. A pogo-pin socket and fixture allows a quick and simple way to connect the IOX module to your development hardware and perform debug and gang programming.

What is included?

• Qty (1) ABBY-IOX-xxx module. The 'xxx' refers to the supported serial bus (I2C, UART, or SPI).
• Qty (4) 8 pin 1.27mm (0.05") male headers.