Was looking into grabbing a capture card for my New 3DS XL, and I started wondering why there weren't more instructions on how to build capture cards. People create custom PCBs for all sorts of things! So I was was a bit surprised that Loopy and Optimize are the only players in town.
So I thought... why not try and build my own from scratch, as a learning experience?
Looking at the instructions for installing the Optimize New 3DS board, there are a number of test points to solder the ribbon cable to. Comparing that with 3DBrew's lower screen dump it looks like we've got 24bit color with an HSYNC, VSYNC, and CLOCK, and a few other points that I don't know about. Guess I'd need to use an oscilloscope to measure what's going on at those unknown points.
Open questions:
- There's only one set of 24 bits for color, so I'm guessing one of the unknown points uses a signal to differentiate between top/bottom screen? How else would that even work?
- Even if I can measure the unknown test points, how do I determine what they're actually used for? Guess I'd just need to experiment and figure it out?
- Since I'm still new to PCBs, I'm not sure what component/chip you'd need to convert the parallel data to a serial stream that can go out over USB. But it looks like something similar to a PISO shift register would do the trick? I've also seen some talk about using a FPGA for this task.
Once you get the serial data flowing through the USB, you just need to write a driver/software on the Windows side to interpret the data, which should be straightforward (maybe you could use the HID api).
Anyone have any experience poking around this area, if this was something I wanted to try out myself?
Thanks,
-AKP