Broadcaster/observer low level implementation

RE: Broadcaster/observer low level implementation

Michael Lamming — Sat, 04 Oct 2014 03:44:06 GMT

Did you guys get this to work ok?

RE: Broadcaster/observer low level implementation

daveln — Mon, 04 Aug 2014 02:39:27 GMT

/LENGTH (6 bits) --> Length(6bits)/ NRF_RADIO->PCNF0 |= (1 << RADIO_PCNF0_S0LEN_Pos) | / * 1 byte / (8 << RADIO_PCNF0_LFLEN_Pos) | / 6 bits / (0 << RADIO_PCNF0_S1LEN_Pos); / 2 bits */ 1)why you set 8 to RADIO_PCNF0_LFLEN_Pos, not 6?

RE: Broadcaster/observer low level implementation

FormerMember — Wed, 14 May 2014 12:56:45 GMT

Paulo, I guess at some point of time you were wondering why the third byte in there received data is always 0. Did you figure out why? While playing around I found that your configuration of PCNF0 wasn't correct, because you assumed wrong endianness. Here's the fix. [code type="xml"] /* Configure header size. * * The Advertise has the following format: * RxAdd(1b) | TxAdd(1b) | RFU(2b) | PDU Type(4b) | RFU(2b) | Length(6b) * * And the nRF51822 RADIO packet has the following format * (directly editable fields): * S0 (0/1 bytes) | LENGTH ([0, 8] bits) | S1 ([0, 8] bits) * * We can match those fields with the Link Layer fields: * S0 (1 byte) --> PDU Type(4bits)|RFU(2bits)|TxAdd(1bit)|RxAdd(1bit) * LENGTH (6 bits) --> Length(6bits) * S1 (0 bits) --> S1(0bits) / NRF_RADIO->PCNF0 |= (1 << RADIO_PCNF0_S0LEN_Pos) | / 1 byte / (8 << RADIO_PCNF0_LFLEN_Pos) | / 6 bits / (0 << RADIO_PCNF0_S1LEN_Pos); / 2 bits */ [/code]

RE: Broadcaster/observer low level implementation

Arnaud Waels — Fri, 14 Mar 2014 15:09:18 GMT

Yes i agree it's the opposite as here. I'm conscious low level is not trivial ! Thank you for those detailed links to doc.

RE: Broadcaster/observer low level implementation

Ole Morten — Fri, 14 Mar 2014 14:55:04 GMT

This is really the complete opposite question than here, so it would have much better off separately. However, you may have use in taking a look at the packet configuration in the example here, as that would be very similar for an advertiser. In addition, I'd recommend you to read the RADIO chapter of the nRF51 Reference Manual thoroughly, read the appropriate parts of the Core Specification, primarily Volume 3, Part C, section 9.1 and 11, and Volume 6, Part B, section 2.3 and 4.4, and take a look at the radio_example in the SDK, as well as this here. What you plan to do isn't trivial, but should be perfectly doable if you read up a little first.

If you have any further, specific questions, I'd recommend you to post them separately.

RE: Broadcaster/observer low level implementation

Arnaud Waels — Fri, 14 Mar 2014 12:53:35 GMT

Hi Ole

Since the previous post, i'd like to implement the low level advertising part.

Which one is the Nordic S110 low level library that implements low level broadcasting ? Or is there a Nordic lib else than nrf51.h or an existing documentation that i can study as a starting point, in order to understand how S110 implements low level broadcasting ?

Thanks in advance, Arnaud

RE: Broadcaster/observer low level implementation

sashi — Tue, 28 Jan 2014 22:55:36 GMT

Answering my own question.

setting NRF_RADIO->DATAWHITEIV = (37); for say channel 37 does work correctly

RE: Broadcaster/observer low level implementation

sashi — Tue, 28 Jan 2014 21:44:51 GMT

Can you post up a fixed version of your main.c. Your posed code so far has been useful. I'd like to see how you did it. I'm currently setting NRF_RADIO->DATAWHITEIV = (channel << 1) + 1; but this doesn't seem to do it. also tried setting to just the channel, as suggested below and also no sucess.

RE: Broadcaster/observer low level implementation

Paulo Borges — Mon, 23 Dec 2013 03:09:14 GMT

Thank you! Setting the DATAWHITEIV register did it.

About your question, no particular reason. In my current version, I already replaced all of them with functions.

RE: Broadcaster/observer low level implementation

Ole Morten — Tue, 03 Dec 2013 16:07:19 GMT

Your code looks good in general, and I suspect that the only thing you're missing is to set the data whitening initialization vector. See section 3.2 in the Core Specification, Volume 6, part B.

Setting this on the nRF51 can be done by just setting the DATAWHITEIV register the channel number (i.e. 37 for the first advertising channel). Doing so, it seems to me that your code is working fine.

Just out of curiosity, is there any particular reason you're using defines instead of regular functions?