Hacking hardware for chumby

From Chumby Wiki
Revision as of 11:54, 12 December 2007 by Markf (Talk | contribs)

Jump to: navigation, search

Note - this page is for hacking of "Ironforge" production hardware.
For information about alpha prototypes, please see Hacking hardware for Foo/Katamari.

What questions do you have about hacking the hardware?

Please post questions here, and someone will attempt to create a sub-page to answer it! Or, check out the forum to see if your question has already been answered.

What's in a chumby?

  • 350MHz Freescale iMX21 MC94MX21DVKN3 ARM9 controller Datasheet Technical Information
  • Samsung 64MB SDRAM on 32-bit data path
  • Hynix HY27US 64MB NAND Flash ROM
  • Three USB 2.0 full speed ports, one internal, two external
  • Xterasys 3135G 802.11g USB Wifi adapter (ralink chipset)
  • DataImage 320hx240v TFT display with touchscreen
  • Texas Instruments TSC2100 Programmable Touchscreen Controller with Stereo DAC Datasheet
  • 2W stereo speakers, with headphone jack
  • Built-in microphone
  • "Bend" switch
  • Kionix KXP74-1050 3-axis accelerometer Datasheet Specifications
  • STMicroelectronics STR711FR0/1 ARM7 "crypto" processor Datasheet
  • Soft-switch on power, controlled by crypto processor
  • TTL serial port @38400 8N1

Power requirements

The chumby uses a very standard 2.1mm I.D. x 5.5mm O.D. x 9.5mm Female (P-5) barrel connector and runs off 1A at anywhere between 6.5 VDC and 14.5 VDC.

Each Chumby ships with a "wallwart" power supply with US-style prongs; however, it's easy to find a compatible power supply with other form factors. Search on "12 volt portable power" for some options. Make sure the power supply provides at least 1 amp (1,000 MA). If you supply less than 1 amp, you'll have an unhappy Chumby that won't display properly, and might make some funny noises!

If you purchase an additional power source, you will need to match the DC power jack on the Chumby. Radio Shack's part number #274-1569 works fine as a power connector, though a tiny bit longer than the plug that comes with the Chumby. Solder the hot side to the middle of the connector, and the ground shield to the sleeve of the connector.

There is a 9 volt battery connector located in the base of the Chumby. This battery will power the unit for a short time during power outages.

Rechargeable Battery Options

In addition to a standard rechargeable 9 volt battery, the Energizer Universal Battery for picture frames (ER-PHOTO) is small enough to be inserted into the base of the Chumby after removing some of the filler material. This battery is rated at 2000mAh with tips for 9V and 12V. In casual testing it has produced up to 3 hours of normal Chumby usage, and can be used while the battery is plugged in and charging. In fact, the power cord for the ER-PHOTO battery appears to be interchangeable with the standard Chumby power adapter, so the Chumby adapter can be used to charge the battery as well.

The ER-PHOTO is available at most electronics retailers for roughly $50.