Hi,

I have performed the following tests on PCBAs #2, #3, #5 and #6:
* power up and check current, all boards around 0.6A
* connect JTAG and flash bitstream, BIOS and filesystem with demo MilkDrop 
rendering firmware and patches
* power cycle the board
* check that the board boots from the flash and renders the default patch
* check that the pushbuttons are reponsive and can be used to select another 
patch
* connect an audio source to the line input, check that the patch reacts
* connect Ethernet, reboot the board and use the serial console to initiate a 
netboot from the BIOS prompt
* load a Linux kernel and initrd through the Ethernet network and check that 
it boots up to running a shell

All the boards passed the tests except PCBA #3 which could not netboot. The 
Ethernet carrier was detected and the autonegociation worked, but the board 
failed to send packets. After inspection, I found out that pin 18 (TXD1) of U2 
was not correctly soldered. I manually re-soldered it, and netboot and Linux 
worked.

A similar error (not covered by the tests above) was found on PCBA #5 where 
pin 4 (D) of U4 was not properly soldered either. We might need to review the 
SMT soldering process to reduce the occurence of these problems. Or are we 
within the normal failure rate of SMT lines?

About the substitution parts listed on [1]:
* both Ethernet connectors (J4) are OK
* both JTAG headers (J6) are OK
* both power jacks (J11) are OK
* both VGA connectors (J17) are OK
* for the memory card connector (J19) the Molex device seems better. Although 
others can be mounted and probably made to work, their metal latch sometimes 
gets stuck and sometimes falls on the components creating opportunities for 
short-circuits if the board is powered up. The Molex device opens/closes very 
smoothly and the metal latch stays in place and does not fall on the board.
We may also want to design the case so it blocks the latch and prevents it 
from reaching the components. This can also be useful with the Molex 
connector, so the latch cannot be manually pushed to create short-circuits.

Sébastien

[1] http://en.qi-hardware.com/wiki/Milkymist_One_RC1_BOM
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