Bat Country's "Thank You DJs" Special!





The interactive transcript could not be loaded.



Rating is available when the video has been rented.
This feature is not available right now. Please try again later.
Uploaded on Oct 29, 2011

Note: Because some people can't seem to offer constructive criticism, comments have now been disabled for this video. Cheers!

In a rather unorthodox turn, our lead engineer has been screwing around with amateur electrical engineering by figuring out how to read a DJ Hero turntable on a PC rather than doing what he's SUPPOSED to be doing and modding Minecraft.

We think it's okay, though. Who hasn't wanted a 55-inch Etch-A-Sketch with 10-inch Dials? That's right. EVIL SANTA. Don't be like Evil Santa, enjoy the giant Etch-A-Sketch.

Plus, if you watch, you might get a peek at our next Minecraft mod...


The DJ Hero turntable module is a pretty smart little device. It's based on a Microchip PIC polling an optical encoder and three buttons. The optical encoder is mounted on the bottom of the free-spinning turntable and is triggered by a toothed rail running along the inner edge of the bottom plastic shell of the turntable module itself. It also takes input from a momentary switch which shorts an I/O pin to Ground if the turntable module is plugged in on the left-hand side of the center deck.

DJ Hero turntable modules communicate over I2C. The right-hand turntable will respond at address 0x0D, the left-hand turntable (by virtue of its depressed momentary switch) will respond at address 0x0E.

Write a single byte of 0x00 to the turntable module to reset the send buffer, then issue a request for 23 bytes. The purpose of the first 19 bytes is unknown, but byte 20 contains the turntable button state in the least significant three bits in the order G-R-B, byte 21 contains the turntable platter distance traveled since the last inquiry, and byte 22 contains the sign of the distance traveled (positive clockwise, negative anti-clockwise). Byte 23 is always zero.

Turntable modules have been found to respond to inquiries as frequently as every 2ms, allowing upwards of a 500Hz polling rate, which is more than often enough to ensure that a human-spun platter will never travel fast enough to cause sign wrap-around.

In our case, we're using a Teensy 2.0, which is an Atmel ATMega32U4, running the Arduino bootloader, on a small carrier PCB. with pin headers. Schematics are considered largely unnecessary insofar as the LEDs and micro-switches are wired up as one might expect based on the Teensy 2.0's "Blink" demo, and the turntables themselves can connect directly to the I2C bus without needing pull-up resistors.

Any questions specific to DJ Hero turntable PC interoperability can be directed to rholtz at batcountryentertainment.com.

  • Category

  • License

    • Standard YouTube License
Comments are disabled for this video.
When autoplay is enabled, a suggested video will automatically play next.

Up next

to add this to Watch Later

Add to

Loading playlists...