[Cryptech Tech] PCB prototyping machine [Was: BCP prototyping machine]

[Павел Шатов]

On 25.02.2015 19:05, Warren Kumari wrote:
> On Wed, Feb 25, 2015 at 2:35 AM, Павел Шатов <meisterpaul1 at yandex.ru> wrote:
>>
>>
>> Yes, that is what I suggest. Have you seen my suggestion to use CPU+RAM
>> module from http://www.imx6rex.com/ on the list? This module can be the core
>> module of our Alpha Board, that end users are not supposed to modify.
>
>
> I'm a little uncomfortable with the "that end users are not suppose to
> modify" wording there.
> I'm assuming that you are just meaning just for the Alpha Board, and
> that this is simply a ready made, convenience option? And that it
> would be replaced with a non-prebuilt solution later in the project?
>
> I realize I may be being overly picky, but use of the words "are not
> supposed to modify" and suggestions to buy a ready made widget with
> all sorts of built in magic sets of alarm bells.

Warren, let me explain this. "end users are not supposed to modify" 
means "I doubt that anyone will ever want to re-design a 12-layer PCB 
with DDR-3 memory interface".

The core of our Alpha Board is CPU + FPGA bundle. Having a CPU implies 
having some RAM for it too. In case of i.MX CPU (which is used in Novena 
and which we are going to use in Alpha Board) we need DDR3-1066 memory, 
so we in fact need to develop a board with CPU + RAM + FPGA. Such a 
board requires very much effort to layout. That i.MX module that I 
suggested to use is open source. It contains the CPU and RAM on one 
small board, so we will only need to develop baseboard for this module 
with FPGA of our choice. They have schematic, layout and all the 
necessary information on their website. We can download it and inspect 
for anything suspicious. If we don't trust them, we can use their layout 
to order boards from company X, their bill of materials to buy 
components from company Y and then ask company Z to solder them for us. 
I've already told that our baseboard (carrier) for this module can have 
expansion connectors, so end users may actually develop their own 
extension modules and connect them to our system. But I don't actually 
think that anyone will want to re-design the CPU+RAM core module though. 
You can get a basic idea of required amount of effort to do this here: 
http://www.imx6rex.com/2013/11/how-long-it-took-to-design-the-imx6-rex-module-prototype/

--
With best regards,
Pavel Shatov