[bushing]

[quote author=donaldson link=topic=216.msg1832#msg1832 date=1274712623]...does not exist. After some extensive detective work, I can say with some certainty that although the processor may sport a second USB port (based on specifications), it's not been traced out onto the processor DDR2 board. If you look at the pic, you can see the WIFI port and the docking port. You are looking at only the D+ and D- lines. Each line comes out on two side-by-side pins. NOWHERE ELSE ON THE DDR2 PROCESSOR DO WE SEE THAT SIDE-BY-SIDE PIN CONFIGURATION. Meaning, unfortunately no other usb port. Sucks. [/quote]Broaden your search.

(I think the JTAG lines are also brought out to the card edge, but I'm not sure where. Probably 5 out of the dozens of pins that aren't routed on the main board, but it's better than having to try to tap them under the chip.)

 

[bushing]

[quote author=donaldson link=topic=216.msg2415#msg2415 date=1274913763]@bushingAwesome. How did you see it! I had totally discounted those lines for sure. Credit goes to you 'cause that is the second USB port. NOw tell me how you know (and more importantly) what else you know! [/quote]

Not much. I actually hooked up my FTDI breakout board to those two pins before I cracked the unit open, and was surprised not to see any debug spew as the device booted -- I then opened it up and saw the RXD/TXD test points labelled on the CPU card, and beeped those out to the test points on the back of the PCB (J17). There was no continuity between either of those points and any pin on the 30-pin connector, so I decided it wasn't UART 0, at least ... I connected up my FT232RL up to those pads and got all the bootup debug spew I expected, so I decided that mystery was solved (the mystery of where UART0 was).Those two pins on the 30-pin are obviously connected to *something* -- they even have 15K pull-up resistors on them. 15K didn't mean much to me, but when I went and traced the other lines to the other internal USB pads, I noticed that they also had a 153 resistor on each line -- and I didn't see those values anywhere else, so it seemed like it was worth a shot. (I've seen some devices be sneaky and run serial RX/TX lines over USB connectors before -- this is the first time I've seen the reverse!) I tried connecting the two data lines one way and got some error message about a failure to enumerate usb2, so I swapped the D+/D- and the thing enumerated. No secret manual here, sorry

I would really like to figure out which of the pins on that card edge are JTAG, though.Are you sure about those video signals? It seems like one of these pins *has* to be 5v out, but I was afraid to actually pull current from either of those pins.