Any brave dive computer download testers out there?

[Sébastien Dugué]

Thanks Jef, this may indeed be a good starting point.

Sébastien.

On Thu, Apr 19, 2018 at 10:20 AM, Jef Driesen <jef at libdivecomputer.org> wrote:
> On 2018-04-19 09:42, Sébastien Dugué wrote:
>>
>> On Thu, Apr 19, 2018 at 1:50 AM, Linus Torvalds
>> <torvalds at linux-foundation.org> wrote:
>>>
>>> On Wed, Apr 18, 2018 at 4:18 PM, Linus Torvalds
>>> <torvalds at linux-foundation.org> wrote:
>>>>
>>>>
>>>> Hmm. Which IRDA chip is it that is in the Uwatec dongle?
>>>>
>>>> Is it perhaps the MosChip MCS7780? You'd know, because then it would
>>>> be using USB ID 9710:7780. That seems to be the common case.
>>>
>>>
>>> Hmm. Googling around, I see that it might also be the Sigmatel
>>> Stir4200 (USB ID 066F:4210).
>>>
>>> That actually has better documentation, and shows exactly the framing
>>> for the normal MIR format (which it would be for the normal 9600
>>> baud). I suspect the MCS7780 needs that same format, it's just not
>>> documented as well.
>>>
>>> The packet wrapping looks like this:
>>>
>>>     0x55 0xaa 2-byte LE length, 0xC0*n  .. escaped data .. 2-byte LE CRC
>>> 0xc1
>>>
>>> and from what I can tell, the Stir4200 also resets to sane default
>>> values (9600 baud SIR).
>>>
>>> But you may have to do some USB control transfers to set the data
>>> direction. It *looks* like the MCS7780 is simpler and defaults to just
>>> "automatic data direction" (which presumably just means "send if there
>>> is TX data, receive otherwise").
>>
>>
>>   Yes, but to me talking to the chip is the easy part. I'm more concerned
>> about implementing enough of the irda protocol stack to be able to talk
>> to all those embedded stacks.
>
>
> I discovered this a while ago:
>
> https://github.com/Diveboard/DC-agent/tree/master/3d-party/irda_mac
>
> It seems to be based on some minimal IrDA stack for micro-controllers:
>
> http://web.archive.org/web/20061124205138/www.blaulogic.com/pico_irda.shtml
>
> This is probably a good starting point!
>
> Jef