Buy Online - AxiCat


The AxiCat is a high-performance, professional multipurpose USB-I2C/SPI/1-Wire/UART/GPIO interface adapter.


  • Quickly hook up I2C and SPI chips to your Linux or Window PC. Check out your I2C and SPI chips without first having to develop specific firmware on a development board or an embedded system.
  • Use your AxiCat as an in-system programming tool for AVR 8-bit microcontrollers. It only takes an AxiCat and five jumper wires to gain full control over flash memory, EEPROM, lock and fuse bits of your AVR microcontroller.
  • Need a serial interface for monitoring or communicating with an embedded system, microcontroller or other device? Turn your AxiCat into a USB-to-serial adapter without the overhead of yet another set of COM-ports. AxiCat features two serial ports that you can use with any terminal program that can interact with network ports (PuTTY, netcat, Hyperterminal, ...).
  • Deploy as a generic development board for your AVR-based project. The bootloader enables quick downloading of your firmware under development.
  • Embed AxiCat in your hardware to add a powerful interface adapter.
  • Double your money: take advantage of all aformentioned applications at 3.3 V and 5 V.


  • Multipurpose I/O card with USB interface.
  • High-performance - all interfaces can operate concurrently while executing I/O commands back-to-back avoiding inter-command delays.
  • Selectable 3.3 V and 5 V I/O voltage levels.
  • 17 bidirectional general-purpose I/O pins with programmable pull-up.
  • 2 fully independent serial ports.
  • SPI bus, master function, 4 slave select lines.
  • I2C bus with pull-up resistors, master and slave function, support for repeated start, arbitration, clock stretching, device probing.
  • 1-Wire bus, master function, strong pull-up control, accelerated enumeration and probing of 1-Wire slaves.
  • USB bus-powered.
  • Support for USB remote wake-up.
  • 26-pin header is sufficiently compatible with Raspberry Pi to interface with many add-on boards.
  • Enables connection of Swiss Pi, PiWire+, AbioCard and other add-on boards for Raspberry Pi to a PC.
  • Four mounting holes.
  • Integrated bootloader enables easy upgrading of firmware.
  • Powerful 12 MHz ATmega164A/324A/644A/1284 microcontroller.
  • General-purpose development board for Atmega microcontroller projects.
  • AxiCat server program enables network and local access using an easy protocol.
  • AxiCat Server enables use of Python, PHP, C, C++, and other languages to program the card.
  • Prototyping of I2C slave functions.
  • Use as in-system programming tool for AVR 8-bit microcontrollers.
  • Open source firmware and software.


The 26-pin header offers seventeen digital general-purpose input/output (GPIO) pins, two UARTs, a full-fledged I2C master and slave function, a SPI master with 4 slave select lines, and a 1-Wire master with accelerated enumeration and probing of 1-Wire slaves and strong pull-up control.


The I/O interface has the capability to work at two different voltage levels: 3.3 V and 5 V. The jumper setting on the 3-pole header determines the voltage level. Thanks to the selectable voltage level the AxiCat can interface with a wide range of chips, peripherals, single board computers and electronic interfaces.

Add-on boards designed for Banana Pi, Orange Pi or Raspberry Pi may be connected to the AxiCat. This opens the door to a number of interesting applications like production testing of add-on boards on a Linux PC or Windows PC.

Unlike many other adapters in the market, the AxiCat features a truly asynchronous design that enables all interfaces to operate concurrently while executing I/O commands back-to-back, avoiding inter-command delays and achieving the highest throughput possible.


You can find additional documentation in directory /public/axicat/doc and other directories called "doc" in the source code.

Software - AxiCat

AxiCat Server is the main application for working with the AxiCat. This program offers the full set of features of the AxiCat and runs as a network server. It accepts text commands over network ports, so multiple users and programs can concurrently access the AxiCat both locally and remotely.

The AxiCat Server serves as a bridge to programming languages. You can easily control your AxiCat-based projects from Python or any other language with support for network sockets.

AxiCat AVR ISP turns your AxiCat into an in-system programming tool for AVR 8-bit microcontrollers operating at 3.3 V or 5 V. It takes as little as five wires to hook up your target AVR microcontroller to your AxiCat. This program enables full access to flash memory, EEPROM, fuse and lock bits of the target microcontroller. It features loading ans saving of Intel HEX files, changing individual lock and fuse bits, and much more.

MCU Bootloader Tool talks with the AxiCat's bootloader. With this program you can update the main application, plus you can deploy the AxiCat as a standalone AVR development board for creating your own projects. The bootloader tool can read and write flash memory, read and write EEPROM, load and save Intel HEX files, and much more.

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