# LinkM - USB to I2C

**Type:** Product page · **SKU:** COM-09903 · **Brand:** [Sparkfun](https://core-electronics.com.au/brands/sparkfun-australia)
**Page:** https://core-electronics.com.au/linkm-usb-to-i2c.html ([markdown](https://core-electronics.com.au/linkm-usb-to-i2c.html.md))

## Retired product

This product is retired and no longer available for purchase. Search the catalogue for an alternative.

## Description

LinkM is a USB adapter that addresses two of the most frequently-requested BlinkM features. It enables you to program BlinkMs without setting up a separate I/O board, such as an Arduino. It also lets you program or control multiple BlinkMs simultaneously. Plug it in, plug in a BlinkM, fire up the BlinkM Multitrack Sequencer, and start programming BlinkMs. It requires no drivers (when used with most operating systems), additional software or hardware. [BlinkM’s](https://core-electronics.com.au/search/?q=08579) sold separately.

**Features:**

- Driverless. Identifies itself as a USB Human Interface (HID) class device, which nearly every operating system supports without requiring additional drivers.
- Has no exposed components. Its hard plastic case makes it appropriate for long-term installation.
- Synchronizes groups of BlinkMs with a metronome signal so that their patterns do not drift in time (this even works when the LinkM is only connected to a power supply, such as an iPod USB charger).
- Works as a generic USB->I2C device, making it compatible with hundreds of standard I2C devices.
- Contains an I2C buffer chip for driving longer I2C bus cables.
- Open Source firmware, available from Google Code
- Open Source libraries for C, Java and Processing that work on Mac OS X, Windows XP/7 and Ubuntu Linux, also available from Google Code.
- Acts as an I2C master with built-in BlinkM metronome for synchronizing groups of BlinkMs so that their patterns do not drift with time
- Additional I/O pins on the board. AVR hackers can crack open the case to get access to digital I/O pins and use LinkM as a standalone microcontroller platform.
 
**Documents:**

- Product Page
- [Datasheet/Guide](https://www.sparkfun.com/datasheets/Components/LED/LinkM_datasheet.pdf)
- Firmware Source

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/l/i/linkm_-_usb_to_i2c__com-09903__01.jpg)