Usb Host Port


This dosent have much to do with the USB mod, but OMG I HAVE THOSE BATTERIES =o.
 
MAN AM I DUMB

why didn't i think of that :( all that pissing about with DC/DC converters waiting for samples eurgghhhhhhhh
 
techFreak posted on Jul 26 2006 at 09:42 AM said:
Simple solution, good idea. Same thing may work for TV-Out ;) Though it would be quite unnecessary.

Someone said something on here that got me thinking about trying to get TV-Out through the headphone port. I already have a list of parts on Mouser.com that I'm going to order to try this out.
 
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jmetal88 posted on Jul 26 2006 at 08:10 AM said:
techFreak posted on Jul 26 2006 at 09:42 AM said:
Simple solution, good idea. Same thing may work for TV-Out ;) Though it would be quite unnecessary.

Someone said something on here that got me thinking about trying to get TV-Out through the headphone port. I already have a list of parts on Mouser.com that I'm going to order to try this out.
As I said before, they are using the "Video" line as an input to turn off the speaker.

Just cut that trace, and wire the Video to that solder pad. Implement a switch to turn off the speakers.

No need to order parts, it is all there, just connected wrong. I suppose if you wanted a jack with a built-in switch you would need to order one, I don't know as they make a 3.5mm video jack with a normally open single pole single throw switch that has the correct solder pads.

I am glad that people are finally realizing what a bad job GPH is doing at design here, for under $10 we could have had USB host onboard, the VGA and HDTV pins could have been run to the EXT (just a few traces, that is all), and the video would have been on the Headphones port too.

By under $10 I mean that since they designed it from scratch, 5 extra traces and 3-4 surface mount devices would likely cost them only $1 per console (maybe as little as 10 or 20 cents).

Lets not even think about the unused IDE interface and the hardware Divx Encoder that are going to waste, I wonder what the cost would have been for the Conexant chip to be an Encoder/decoder of A/V signals? Then we would have a cheap Archos replacement with full resolution.

I guess this should go in the wishlist of the GP2X upgrades, I don't need a different CPU, I just need this one exposed properly to the world.
 
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nubie posted on Jul 26 2006 at 10:25 AM said:
jmetal88 posted on Jul 26 2006 at 08:10 AM said:
techFreak posted on Jul 26 2006 at 09:42 AM said:
Simple solution, good idea. Same thing may work for TV-Out ;) Though it would be quite unnecessary.

Someone said something on here that got me thinking about trying to get TV-Out through the headphone port. I already have a list of parts on Mouser.com that I'm going to order to try this out.
As I said before, they are using the "Video" line as an input to turn off the speaker.

Just cut that trace, and wire the Video to that solder pad. Implement a switch to turn off the speakers.

No need to order parts, it is all there, just connected wrong. I suppose if you wanted a jack with a built-in switch you would need to order one, I don't know as they make a 3.5mm video jack with a normally open single pole single throw switch that has the correct solder pads.

I am glad that people are finally realizing what a bad job GPH is doing at design here, for under $10 we could have had USB host onboard, the VGA and HDTV pins could have been run to the EXT (just a few traces, that is all), and the video would have been on the Headphones port too.

By under $10 I mean that since they designed it from scratch, 5 extra traces and 3-4 surface mount devices would likely cost them only $1 per console (maybe as little as 10 or 20 cents).

Lets not even think about the unused IDE interface and the hardware Divx Encoder that are going to waste, I wonder what the cost would have been for the Conexant chip to be an Encoder/decoder of A/V signals? Then we would have a cheap Archos replacement with full resolution.

I guess this should go in the wishlist of the GP2X upgrades, I don't need a different CPU, I just need this one exposed properly to the world.

Well, I would still have to order some parts, as I have nothing that uses a 4-pole phono plug, and I don't expect RadioShack to have any (their part selections are kind of sucky lately).


Anyway, I was thinking of using this jack:

http://www.mouser.com/catalog/specsheets/KC-300985.pdf

Although, according to you, the headphone jack is hooked up in a slightly different way than I expected. I would have expected then to use a stereo jack with a normally closed switch, and open it to turn off the speakers, as that seems the most logical route. Are you positive they hooked it up the way that you said? It seems that would pose problems to the left channel of the headphones, plus that would make it a little difficult to wire up my jack, unless the pin 1 - cs connection can be used as a normally open switch.

Also, I would have to wire my own video cable, as none of the existing ones have pinouts that will work with both A/V out and only audio out (I would have to wire it so that when headphones are plugged in, the video signal would be shorted to ground).
 
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jmetal88 posted on Jul 26 2006 at 08:38 AM said:
Well, I would still have to order some parts, as I have nothing that uses a 4-pole phono plug, and I don't expect RadioShack to have any (their part selections are kind of sucky lately).


Anyway, I was thinking of using this jack:

http://www.mouser.com/catalog/specsheets/KC-300985.pdf

Although, according to you, the headphone jack is hooked up in a slightly different way than I expected. I would have expected then to use a stereo jack with a normally closed switch, and open it to turn off the speakers, as that seems the most logical route. Are you positive they hooked it up the way that you said? It seems that would pose problems to the left channel of the headphones, plus that would make it a little difficult to wire up my jack, unless the pin 1 - cs connection can be used as a normally open switch.

Also, I would have to wire my own video cable, as none of the existing ones have pinouts that will work with both A/V out and only audio out (I would have to wire it so that when headphones are plugged in, the video signal would be shorted to ground).
That jack has entirely the wrong connections. Hang on while I find the post with the picture to help you.

It looked to me that the one they are using would suffice for everything but getting the speakers turned off.

The jack they use has flat solder pads along its length, the pdf you showed me has pins at the bottom, I don't think it would work all that well (unless you put it to the other side of the SD as the Vid socket and wire it to the EXT traces, but then you wouldn't have room for the USB mod and you would have 2 headphone jacks).


Here it is, Evildragon opened a MK2 and has posted the pics.

http://archive.gp2x.de/cgi-bin/cfiles.cgi?0,0,0,0,23,1570

I just assumed you had a mk2, if not then maybe you need a MK2 style socket to start your mod.

Nevermind, that is not the picture I was thinking of, I have seen one with a nice close-up of the headphones socket.

I have to ship my GP2X, or I might open it and have a look myself.

Just sold it on ebay, heres hoping it helps me stay financially solvent, I have been sick with the flu for a week and haven't been to work much.
 
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nubie posted on Jul 26 2006 at 10:48 AM said:
jmetal88 posted on Jul 26 2006 at 08:38 AM said:
Well, I would still have to order some parts, as I have nothing that uses a 4-pole phono plug, and I don't expect RadioShack to have any (their part selections are kind of sucky lately).


Anyway, I was thinking of using this jack:

http://www.mouser.com/catalog/specsheets/KC-300985.pdf

Although, according to you, the headphone jack is hooked up in a slightly different way than I expected. I would have expected then to use a stereo jack with a normally closed switch, and open it to turn off the speakers, as that seems the most logical route. Are you positive they hooked it up the way that you said? It seems that would pose problems to the left channel of the headphones, plus that would make it a little difficult to wire up my jack, unless the pin 1 - cs connection can be used as a normally open switch.

Also, I would have to wire my own video cable, as none of the existing ones have pinouts that will work with both A/V out and only audio out (I would have to wire it so that when headphones are plugged in, the video signal would be shorted to ground).
That jack has entirely the wrong connections. Hang on while I find the post with the picture to help you.

It looked to me that the one they are using would suffice for everything but getting the speakers turned off.

The jack they use has flat solder pads along its length, the pdf you showed me has pins at the bottom, I don't think it would work all that well (unless you put it to the other side of the SD as the Vid socket and wire it to the EXT traces, but then you wouldn't have room for the USB mod and you would have 2 headphone jacks).


Here it is, Evildragon opened a MK2 and has posted the pics.

http://archive.gp2x.de/cgi-bin/cfiles.cgi?0,0,0,0,23,1570

I just assumed you had a mk2, if not then maybe you need a MK2 style socket to start your mod.


Actually, I knew that jack had wrong connections. I was inteding to glue it on upside-down and solder leads to the correct pads. And no, I don't have a Mk. II, actually, I have a First Edition. The headphone socket is about half as wide, and has four connections, three on one side (which I assumed were Ground, Right, and Left channels, starting from the outside of the board) and one on the other (which I assumed was a normally closed switch, so that the speakers could be turned on when the headphones weren't connected). I'm guessing now that I'm not correct in my assumptions, and would require further investigation of the headphone jack.
 
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I suppose you could just do it the way you planned, you can use a logic gate to change an open signal to a closed signal I think.

Just completely remove that socket and put yours in there.

I think that the one by itself is left.

And the other side has either Ground, sense, right. Or, Sense ground, right.

Just change the appropriate one to be video. And if you must, jumper the other one to ground.

I think it is too skinny for a switch, I would check it with a camcorder-style video cable (the ones with A/V stereo, also some portable DVD players use them).

If it turns out to not be a switch, then go ahead with plans.

Edit: sorry to be so off topic and forum stealing. (I am talking about internal hacks though, so it should be okay :)).
 
nubie posted on Jul 26 2006 at 10:59 AM said:
I suppose you could just do it the way you planned, you can use a logic gate to change an open signal to a closed signal I think.

Just completely remove that socket and put yours in there.

I think that the one by itself is left.

And the other side has either Ground, sense, right. Or, Sense ground, right.

Just change the appropriate one to be video. And if you must, jumper the other one to ground.

I think it is too skinny for a switch, I would check it with a camcorder-style video cable (the ones with A/V stereo, also some portable DVD players use them).

If it turns out to not be a switch, then go ahead with plans.

Ah, I see what you mean. So they are grounding Sense to turn off the speaker? That kind of makes sense. It might be a little tricky to wire up, though. I'd have to think about how I'd do that.
 
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Hmm... I'm wondering if the internals of the GP2X headphone port are similar to this:

http://www.mouser.com/catalog/specsheets/KC-300870.pdf

If so, then I might just be able to bend a small wire around the outside plug of the headphone jack and connect that to sense, so that whenever something is plugged in, sense is grounded. I then loose the need for any TTL circuits or switches.
 
jmetal88 posted on Jul 26 2006 at 10:21 AM said:
Hmm... I'm wondering if the internals of the GP2X headphone port are similar to this:

http://www.mouser.com/catalog/specsheets/KC-300870.pdf

If so, then I might just be able to bend a small wire around the outside plug of the headphone jack and connect that to sense, so that whenever something is plugged in, sense is grounded. I then loose the need for any TTL circuits or switches.
That was exactly my thought! (great minds think alike and all that :)).
 
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ignoring the speaker turn off(could always just add a mod to manually turn them off with a switch) could you still use the headphone jack for headphones and mini plug A/V cable like this one http://www.amazon.co.uk/gp/product/B0000C4...ce&n=560798 I have a RCA to mini plug cable for my creative zen, if I could mod the gp2x to use that it would be sweet. Then I could play games on the tv like the good old days. But if I can't use headphones(and make a switch to shut off the sound to the speakers) then I doubt I would do it.
 
oqnet posted on Jul 26 2006 at 10:32 AM said:
ignoring the speaker turn off(could always just add a mod to manually turn them off with a switch) could you still use the headphone jack for headphones and mini plug A/V cable like this one http://www.amazon.co.uk/gp/product/B0000C4...ce&n=560798 I have a RCA to mini plug cable for my creative zen, if I could mod the gp2x to use that it would be sweet. Then I could play games on the tv like the good old days. But if I can't use headphones(and make a switch to shut off the sound to the speakers) then I doubt I would do it.
Good question, I would investigate what effect if any grounding the Video would have on anything.

Or of course just make a dongle using a 4 conductor plug, and wire the correct 3 to a headphone jack.

If you can find a 90 degree angle one it would be nice, and it would help you use the headphones with plugs that hit the case on the GP2X because they are too big.
 
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nubie posted on Jul 26 2006 at 11:42 AM said:
oqnet posted on Jul 26 2006 at 10:32 AM said:
ignoring the speaker turn off(could always just add a mod to manually turn them off with a switch) could you still use the headphone jack for headphones and mini plug A/V cable like this one http://www.amazon.co.uk/gp/product/B0000C4...ce&n=560798 I have a RCA to mini plug cable for my creative zen, if I could mod the gp2x to use that it would be sweet. Then I could play games on the tv like the good old days. But if I can't use headphones(and make a switch to shut off the sound to the speakers) then I doubt I would do it.
Good question, I would investigate what effect if any grounding the Video would have on anything.

Or of course just make a dongle using a 4 conductor plug, and wire the correct 3 to a headphone jack.

If you can find a 90 degree angle one it would be nice, and it would help you use the headphones with plugs that hit the case on the GP2X because they are too big.
I haven't opened the gp2x to see if theres room but it might be worth putting the jack a inch or so away from the headphones and just wiring the tvout to that and leaving the headphones alone.
 
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I think with the way I've got it figured out, it would work with headphones and A/V, but I'd need a custom A/V cable, as the pre-made ones (according to pinouts.ru) all have the ground in the wrong half of the jack to work with standard headphones as well. I'm hoping that grounding the video won't have any adverse effects, but I don't see why it should since the video signal should be turned off anyway whenever the TV-Out is disabled.
 
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