Am 13.12.2012 16:09, schrieb Antti Palosaari:
> On 12/12/2012 11:34 PM, Frank Schäfer wrote:
>> Am 12.12.2012 22:25, schrieb Frank Schäfer:
>>
>> ...
>>> Am 11.12.2012 21:59, schrieb Antti Palosaari:
>>>> See current af9015 driver as example how driver makes decision which
>>>> variant of NEC is used. You will need something similar. Read all 4
>>>> NEC bytes from the hardware and then use driver to make decision which
>>>> variant it is.
>>> Yes, checking for inverted address and key code bytes would be a
>>> possibility...
>>
>> The problem here is of course, that we have to configure the device
>> first.
>> So we need to know the protocol variant before getting any bytes from
>> the device...
>
> No, you now don't see the point correctly. If you read 4 byte "full
> NEC" code from the hardware, you will not need to know which variant
> it is for configure hardware. 4 byte, full NEC, presents all the
> variants.
>
> Think it like NEC code is always 4 byte long as lower layer. All NEC
> remotes sends 4 byte codes regardless which variant. In receiver side,
> after decoding there is also 4 byte always. Variants are done very
> upper layer after decoding.
>
> Let me take some existing examples:
> ------------------
> rc-trekstor.c: { 0x0084, KEY_0 },
> This is actually 1 byte NEC, which is device id == 0.
> 4 byte real code is: 00 ff 84 7b
> ------------------
> rc-terratec-slim-2.c: { 0x800d, KEY_0 },
> This is normal, traditional, oldest, most common, 2 byte NEC.
> 4 byte real code is: 80 7f 0d f2
> ------------------
> rc-terratec-slim.c: { 0x02bd09, KEY_0 },
> Extended NEC, quite common, 3 byte NEC.
> 4 byte real code is: 02 bd 09 f6
> ------------------
> rc-tivo.c: { 0xa10c8c03, KEY_NUMERIC_0 },
> "full" NEC, 4 byte NEC.
> Not very common, but coming slowly more popular.
> 4 byte real code is: a1 0c 8c 03
>
>
> As you can see all NEC variants could be presented as 4 byte NEC. Even
> the "one byte NEC", which comes in that case (rc-trekstor.c) "00 ff 84
> 7b" as 4 byte real notation.
Sure, we always get 4 bytes from the hardware.
But there must be a difference on the hardware level, otherwise the
em2874 wouldn't use different values for reg 0x50 (and Matthew should
see messages for ALL keys).
Regards,
Frank
>
>
> regards
> Antti
>
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