That Ext Port :)


racoon

Member
Joined
Nov 18, 2005
Messages
236
Hi people...
Just heard that the EXT port may have a USB Host functionality, but lets consider that as a rumor only for now, Ive got a question:
According to this site:

http://wiki.gp2x.org/wiki/EXT

...there are two connectors for 3.3V power, I own a LG phone and recharge as well as "usb" it over its EXT port... may I simply use my phone recharger (appearantly 3.3V) for my GP2X? Has anyone tried that? It should work, shouldnt it??

thanks
racoon
 
Back feeding 3.3V up the EXT port may work, but then again it may fry the unit if it wasn't designed for that as it'll be sucking much more current than what the connector and possibly the pcb tracks were designed to carry. You could also damage other components in the 2X which were not meant to have voltage supplied to there outputs (for example).

Bottom line is that it may work, but your on your own - if it fries the 2X, you'll have to fix it, as it definitely won't be covered under warranty.

The USB connections are apparently from a Korean with good contacts with GPH, so *could* be the real deal.
 
Ok, so I have to lookout for another 3.3V adaptor... just figured out the EXT spec is 3.3V but the LG adaptor got 4.0V+ ....

Do you know who makes such universal 3.3V adaptors because I am unable to find general devces, I only find stuff suited for a specific gadget/phone/whatever...

Thanks for any help
 
A 3.3V adaptor is ideal, but a decent 3V adaptor will do fine, as they are never that accurate unless what you buy costs in the region of 3+ digits (with the decimal point after the 3rd for the pedantic people here...)

I use a 1.2A adaptor with switchable heads, polarity and voltage from Maplins for example. Just make sure it's 3V, centre negative, and preferably 1A or higher.
 
when i built my serial adapter for my gp2x, i fed power to the 3.3v pins to see if it would work, and it did, but alas the power-regulating transistor in use on the (custom) board we made to do ttly->rs232 started to heat up rather too much, indicating resistance/draw on the EXT pins, so we disabled that feature. it did work for about 15 minutes, however .. would probably be good to develop that feature on your own cable with some seriously well-designed power-regulation ..
 
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