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Hardware > ampz's keyboard

#3895 - pollier - Wed Mar 12, 2003 6:57 am

this might as well be a PM to ampz, but for open-forum-style,

Anyways, I finally got off my butt and decided to solder this keyboard today, and then I look at the site's photo and it looks completely different--it looks to me like you're using pins 7 & 9, although those aren't mentioned on the site.

Blah, point is, it doesn't work for me ::shrugs:: This always happens anyways, but I checked the pins and whatnot; voltage is nice and stable at .7 volts (???) and I checked my GBA connector--it's fine, so any suggestions as to where I might have gone wrong?
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#3923 - ampz - Wed Mar 12, 2003 10:03 pm

Two wires in the cable are not used, I just soldered them to pin 7 and 9 on the keyboard since thoose solderpads on the keyboard are not connected to anything. Didn't want to just cut the wires...

0.7V is totally wrong, it should be 3.3V, check your VCC connection... (pin 1).
Most link cables do not have a pin 1 at all. Some link cables w/o a pin 1 can be modified, ie. you can open up the connector, and move an unused pin to pin position 1.

EDIT
Oh, and do NOT look at the wire colors in my pictures, there is no guarantee that they are the same as your cable. Use a DMM to check wire-to-pin connections.

#3937 - pollier - Thu Mar 13, 2003 6:53 am

It's very strange. I'm using a 1k resistor, everything is wired properly, and I'm still getting .7 volts. My connector luckily has all 6 pins wired, and pretty much the only difference on my circuit board from yours is that mine says "0005" instead of "0012" in the photo. Do you have any idea where this .7 volts might be coming from? Some kind of hi/low signal? I'm very sure I have the right pins, and I have a standard platinum GBA...

...strange indeed.
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#3988 - ampz - Fri Mar 14, 2003 4:16 pm

Check that VCC connection. (pin1)
Also, you might wanna check the GND connection.

Voltage between VCC and GND is supposed to be 3.3V