[chbot] Opps sorry - that subject should be "More cheap ARM boards!"

[Paul Davey]

>
> My main question always is - what is the software API for the SPI/I2C
> interfaces?
>

The software interface to the SPI/I2C on these will be either (If you write
bare metal code and do not use linux) the direct register access that will
be somewhat similar to most micros and descriptions will be available in
the programming manual for the A10, or (If you use linux) the interface
will be the linux stack for that device, the SPI stack for SPI and I2C for
I2C I believe there are drivers that expose userland interfaces to these
kernel interfaces however most of these require adding definitions for the
devices to the kernel board init routine so you have to recompile the
kernel to change the devices.  The linux stacks for these are meant to
arbitrate access to the bus for everything in the kernel so there are
usually delays that will be incurred that are not present on bare metal
microcontrollers since these have no need to share these buses properly.
 Also notice that atleast one of the I2C interfaces is used for the HDMI
display for the EDID interface.

Paul
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