[Arm-netbook] Open source Allwinner R40 circuit diagrams

[joem]

On 2018-04-13 00:46, Luke Kenneth Casson Leighton wrote:

> superb.  i might point someone i know at these, he may be interested
> to use them.

You are welcome :) 

Now I customize the design into a new minimalist R40 server board: 
https://www.hellosemi.com/KiCAD_Server_Board.html 

This board has 2GB RAM, gbit ethernet, SATA, camera, MIPI display, HDMI,
uSD, 8GB flash, USB OTG, USB 2.0 x 2. Removed are wifi/bluetooth, audio,
mic, Pi connector, IR module. The 8GB flash required a lot of rework as
the BGA pinouts were incorrect in the original drawing. Also I had
duplicate annotation and missing annotations in my previous KiCAD. Added
more footprints where they did not exist from KiCAD libraries. All
footprints were copied to local relative directory because switching
between different PCs is a total pain at this moment with KiCAD. After
all that work, the netlist import works without errors, and viewing 3D
works without errors :) 
Anyone can lay it out now. 
I'm guessing this PCB will come out with a BOM cost less than $20. 

For some reason Allwinner R40 SATA read seems fast but write is very
sloooow. Anyone know?