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chumby:hackerboard

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Powering the Chumby Hacker Board

Power jack

The Hackerboard requires a regulated 5VDC power supply, positive tip, via a 3.5mm OD, 1.4mm ID barrel jack (sometimes referred to as a 3.8mm or 4mm connector). To connect you will need a matching plug, such as this. We suggest <a href="http://www.adafruit.com/index.php?main_page=product_info&cPath=46&products_id=276">a regulated switching supply</a> with over 1000mA output capability. The power required by the board itself is not that high (100mA? check this) but if you plug in a Wifi dongle into the USB port, or an LCD into the LCD expansion port, the power required can easy climb to a 1000 mA. Since the connector is the same as those used in the PSP, you can use <a href="http://www.adafruit.com/index.php?main_page=product_info&cPath=46&products_id=276">PSP power supplies and chargers</a>!

Under no circumstances should you power the device with anything higher than 5V, you will destroy it!

Lithium battery

Needs factchecking

The board can also use a lithium ion/polymer battery for power. The board even has a built-in lipoly charger! (is it activated by default? what charge rate?)

If powering from a lipoly, the chip will boost it to 5V to supply power to one of the USB port s(the top one, on the same side as the power jack) but not to the other two.

Connecting with TTL serial

The chumby has a four-pin, 3v level TTL serial connection port running at 115.2 Kbps. You cannot just connect this to your computer's serial port, parallel port or USB port without a converter. We think the best way to connect is using an FTDI cable which can be easily modified.

Make the cable

http://www.ladyada.net/images/ybox2/propcable33v.jpg

You must use a 3.3v logic level FTDI cable, look for the letters "3V3" or similar on the cable. We also suggest checking with a multimeter that the voltage on the logic pins (everything but Red) is no higher than 3.3V. 5V logic will damage the chumby board, and it would be a shame if it broke before you got to have some fun!

Also, make sure you have an adapter thats a cable, so that you can move around the pins

http://www.ladyada.net/images/ybox2/propcablestart.jpg

Use tweezers to lift up the black connector tabs

http://www.ladyada.net/images/ybox2/propcableremovewire.jpg

Then gently pull out the wires

http://www.ladyada.net/images/ybox2/propcablepullout.jpg

http://www.ladyada.net/images/ybox2/propcableremoved.jpg

Repeat!

http://www.ladyada.net/images/ybox2/rawcable.jpg

Rearrange the wires as shown, so you have Black (GND) then a space, Orange (TX) and Yellow (RX). You can clip the unused pins or cover them with heatshrink. They wont be used. Just make sure you don't have the conductive pins accidentally touch your Hacker Board!!!

:chumby:chumbyftdi.jpg

/home/ladyada/public_html/wiki/data/attic/chumby/hackerboard.1283027147.txt.gz · Last modified: 2016/01/28 18:05 (external edit)