D-Link DIR-615 rev C2 USB port mod

Download svn source code

Run 'make menuconfig' and select platform/profile and other options (usb-core,
usb-storage, usb2.0, block-extroot, etc - all what you want)

Compile image and flash it to router.

Solder usb socket (i soldered horizontal for testing but later i'll replace it with part of usb extender)

Solder usb power. My Dir-615C2 use 5V power source so I just solder a wire from power input to usb +5V line. But I think i'll install dc/dc 0505 isolator instead of this wire.

Solder two usb data line resitors (r237/r230 - 22 Ohms)

Solder pull-down resistors at the bottom of the pcb. Use small 0603 smd 15k resistors (marked as '153').

Solder usb_rref (also known as USB_REXT) 6,19kOhm resistor (A note by another user about what follows: this 6.19 kOhm resistor is already on the board, it is R66 at the corner of U1 on the top side (we can see it on the picture showing the serial header further below). Soldering a resistor on footprint R13 as shown here would be actually a pull-down on EJTAG_SEL, disabling enhanced JTAG, which is already enabled thanks to R11, a zero-ohm resistor connected to 3.3 V supply. In order words, soldering the resistor as described here is like soldering a resistor between the 3.3 V rail and ground. See schematic dir615c1.pdf) (I soldered 4.7K, but later I got a dir-615c1 circuit with usb_rref=6.19K 1%) at the bottom of the pcb near ar9130 processor (look photo). I soldered 0805 size because didn't find 4k7 0603 size at home. If your solder skills not good - ask to solder this in any cellphone repair service (size of 0603 resistor - 1.6×0.8 mm)

Solder serial header (you'll need it :)

Now check pcb... Twice! Connect serial and power router on.......
Wait until device boot and connect flashdrive. If you did all well you'll see at serial console:
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