Quote:
Originally Posted by Tommyxx84
Obviously i'm not going to plug it until i know that wires are set correctly.
The usb cable wires, as known, are:
WHITE: USB DATA+
GREEN (blu wire in my case): USB DATA-
RED: +5V
BLACK: GND
Based on this
Pinout:
I am doing this from memory, so it might not be correct. It is probably documented in mobileread along with the connector layout for a circuit board.
On the kindle models that I have examined, the serial port layouts were designed so that it is okay to short together any adjacent pair of pins. They are in the order (starting at the top on kindle 3) TxD, RxD, GND. The kindle 3 also has a 4th pin at the bottom, which when connected to the GND pin above it, enables +3.7v DC power to the top connector (in the top slot). You should verify the information above before using it.
I'm assuming that, using the picture and "reading it" from left to the right
WHITE: USB DATA+ -> 1st pin from the left
GREEN (blu wire in my case): USB DATA- > 2nd pin from the left
BLACK: GND -> 3rd pin from the left
RED: +5V -> not necessary
Is it correct?
If so, what's the next step?
|
No, it is NOT correct (according to the your wire sigbal descriptions). Even though the photo of your adapter looks like it might be a USB serial adapter, the signals you describe are USB signals, not TTL serial signals. Perhaps that is why there is no green wire? Another problem is that if red really is +5V (as measured with a volt meter or o'scope), your serial adapter may be the wrong voltage.
The whole purpose of a USB serial adapter is to change the signalling protocol AND to shift the voltage levels. If is is indeed such a device, those wires are not as you described, but rather TTL serial Rx, TTL serial Tx, GND, and perhaps a power supply voltage. Read the specs for your device. It you have no docs, look up its make and model (or FCC part number if it has one) on the web...
Or use the "poke and prod" method -- see which wire fluctuates (with an oscilloscope) when you send data to it from a host computer. Do NOT supply power from the host computer to a kindle over this cable. And if the signal voltages are wrong, check out my TTL serial level shifter circuit.