Re: Re: AW: [Paparazzi-devel] Commercial boards

[martin]

Hi,

we should have the PCBs tested by the PCB maker as they usually do.
Additionally we need a test for the entire board.

- parts are populated correctly
- parts are working

We have to make a list on how to test each part on the board and write
test software.

- quarz starts to oscillate
- USB (download) works
- LPCs boot
- LPCs communicate
- GPS is responding, does a fix in reasonable time (dependant on GPS
constellation)
- make Molex short circuit connectors to test pins (eg. connect GPIO1.6
to GPIO1.7) and check for connection bi-directional
- PPM output is there
...

It is essenial to have the boards running correctly when they ship and
to be able to tell once a board is broken (eg. after a crash). We
already spend quite some time finding that out :-)

Someone looking on how to make boards should also find out if the boards
can be made the way they are. Some ground planes eat up a lot of heat
and the soldering is difficult. Also some parts are very close to
others (in the shadow). The GPS rx and the GPS patch most likely need
hand soldering/glueing.

Martin

> Nicolas,
>
> i am looking into production & issues surrounding that for all boards
, that
> are stable , and classix once the few items remaining are sorted .
> in most cases automated testing is mostly by default , to check the
pcb's
> and parts for non functioning bad
> ic's etc , which can be changed before dispatch to the client , and is
now
> done to satisfy regulations etc
> as any pcb made for or in europe has to comply now to RHOS and other
weird
> money making regulations  CE etc
>
> the main problem to get the price down , is to have volume , but you
need to
> weigh the costs of lower output
> being automation and hand soldered i.e labour , the main problem being
to
> set up a pcb automated build system
> can take 2 -3 hours setup time , even though then it can produce a pcb
in
> about 20 - 30 seconds
>
> they don't like setting up for only a hour production run , as it then
costs
> about the same time as 4 hours
> all lost revenue for them , so it's a trade off in small numbers .
>
> anyhow will let you all know once i have the figures worked out , see
what
> Ethan can find out too
>
> i have access to companys in China and Singapore if they are willing
to do
> them , lets see ,  it's all in the numbers
>
> Dave
>
>
>