x41t sata mod problem

[willprice94]

Hello,
I've removed the SATA-to-PATA bridge and soldered on some 30awg enamelled copper wire to a SATA to mSATA converter which is housing a myDigitalSSD, currently I'm having issues getting the drive to boot properly. I managed to get the drive recognised and installed Arch linux, I was getting some errors occasionally when accessing the disk and I believe I was also getting some corruption as some applications were throwing a segfault for no apparent reason.

I desoldered my wires and started again to try and make the mod more reliable making absolutely sure I'd made good connections and hadn't bridges any pads using a liberal amount of no-clean flux. The drive is no recognised in the BIOS but part loads syslinux and then hangs without loading further, or fully loads syslinux and then doesn't fully load the initrd image.

When I boot up into Arch on a memory stick I get the following error in regard to the SSD: end_request: I/O error, previously I was getting some DRDY (or something similar, I can't remember the exact acronym) errors, though the partitions are fully visible. I can't run cfdisk to reformat either.

Any ideas on where the issue might lie?

Tomorrow I shall go over my connections with a loupe and check for bridges and check my connections for continuity.

[twistero]

SATA is a high-speed protocol, therefore very susceptible to noise. There's a reason why proper SATA cables use twisted pairs, ground wire between signal wires, shielding, and are carefully impedance-matched.

The least you should do is to make sure all 4 signal wires are exactly the same length, and twist the differential pairs. It might be a good idea to reuse some of the existing PATA traces.

[willprice94]

I've just tried using an actual SATA connector, but that wasn't much of a success so I've gone back to enamelled copper wire. I've tried soldering on so many times to both the AC coupling capacitors and have torn off their pads (closest to the bridge IC), I just took them off and soldered to the furthest pads (therefore bypassing the coupling caps), I'm currently installing Arch and no weird errors have appeared so I think I might have got it!

The distance I'm wiring over is pretty short, if I was using a SATA cable I'd have to use the copper wire as an intermediate between the pads and cable so I really don't think I'd be gaining much from using it. I think it's fairly likely I'd screwed up the coupling caps when I was soldering before hence the errors. Theoretically it should function OK without them from what I understand (please feel free to correct me on this, electronics is a hobby for me, I'm certainly no expert), but they do provide a bit of a buffer. I suppose they also block DC current, not really sure on that one, but the main thing is that it's being recognised and working, if anyone can provide technical insight I'd be very interested to understand the use of AC coupling on those lines.