Edit: An English product page is up now, you can check it out here: [LINK]

I posted earlier on my blog about the new motor MUX that is being made by a Ukrainian company, HOLIT Data Systems.  I’ve since been able to have a chat with one of the guys behind the site that is selling them.

The technical specs are rather interesting.  From the picture you can see there are 3 motor ports, a connector to the NXT and one to daisy-chain up to 62 more of these devices to each sensor port.  In my original article I mentioned you could connect up to 189 motors to your NXT, I was wrong.  That should be 756, of course, seeing as there are 4 sensor ports on a brick.  I can’t imagine having 189 motors connected to my NXT, let alone 756.  That’s not counting the 3 normal motor ports.

The motor MUX comes with a CD with all the software and instructions necessary to start using it.  Right now it’s all in Russian, which is great if you speak Russian.  However, fear not, they will translate the blocks to English shortly.

• The 1s block is for configuring the motor mux, such as setting the address.
• The 2nd block is a “lamp block”, which I assume would be useful if you connect a little light to the motor port instead of a motor.
• The 3rd block is a normal motor block.
• The 4th block is a move block that controls multiple motors at once.
• The 5th block is an encoder reading and resetting block.

I do have a roughly translated description of the I2C commands and messaging specification which I will publish shortly. Once I have some hands-on experience I will let you know! A ROBOTC and NXC driver will be published shortly thereafter.

Here is the link to the mux’s product page: [LINK] (translated). They cost about $70.

Here is a cool video of the motor mux in action: [LINK].

As you can see it’s pretty trivial to daisy-chain them.  I believe it is also possible to connect normal I2C sensors as well, with the exception of the LEGO Ultra Sonic sensor.

Edit: changed the links to the product page to a more up-to-date one.