is nrf52 dk support 3 wire spi interface

RE: is nrf52 dk support 3 wire spi interface

RK — Sat, 03 Jun 2017 12:09:18 GMT

Great. Well done. Thanks for following up.

RE: is nrf52 dk support 3 wire spi interface

pawan_v61 — Sat, 03 Jun 2017 11:02:13 GMT

my problem was solved thanks for support

RE: is nrf52 dk support 3 wire spi interface

pawan_v61 — Sat, 03 Jun 2017 11:01:47 GMT

my problem was solved thanks for valuable suggestions & information sir

RE: is nrf52 dk support 3 wire spi interface

RK — Wed, 31 May 2017 05:31:59 GMT

it doesn't care - it just stops after it's clocked the number of bytes on the clock line. It doesn't look at the data it clocks, if you say you want to transfer 20 bytes, it clocks 160 times and then stops.

RE: is nrf52 dk support 3 wire spi interface

pawan_v61 — Wed, 31 May 2017 05:29:47 GMT

are you sure the spi transfer data successfully even though I aam not using Miso pin(ie., the master was not receiving any buffer data).In the data sheet the data is transfer when processor generates start & stop tasks . The processor generates start task when data is transfer from master to slave. The processor generates stop task when master receive data from slave to master.But I am not connecting MISO pin so there is no scope of receiving the slave data to master that's why there is no scope of generating stop task. Can you please confirm the processor will generate stop task & data send succesful from master to slave even though there is no data received from slave to master.

RE: is nrf52 dk support 3 wire spi interface

pawan_v61 — Mon, 29 May 2017 13:59:59 GMT

ok thanks for support , i will looking into it.

RE: is nrf52 dk support 3 wire spi interface

RK — Mon, 29 May 2017 12:30:31 GMT

slowly, slowly you add more information about what you're doing. I checked the datasheet for that chip, it's unidirectional SPI, data is only written to it, never read. So again, the SPI interface will work just fine, you just define the MISO pin as 0xffffffff, the driver will work, there is nothing special to do here.

I said, in the link you pasted, that the 3-wire half duplex protocol was not supported. That's the one where one pin does transmit and receive. This is NOT that case with the chip you are using, this is a normal SPI interface where there is no data transfer from the slave, only writes TO the slave. That is supported, so now you need to start looking for your bug.

RE: is nrf52 dk support 3 wire spi interface

RK — Mon, 29 May 2017 12:12:38 GMT

I asked you earlier if it was half duplex and you said it wasn't and you've said twice now that you're just not connecting one pin, ie it's a one-way connection only. Now you've linked to a question saying it is indeed half duplex and I said in that question, and I said earlier here, that isn't going to work.

If you are trying to do bi-directional SPI over one single data line, that is not supported.

RE: is nrf52 dk support 3 wire spi interface

pawan_v61 — Mon, 29 May 2017 10:45:17 GMT

the following link contains the nrf52dk does not support nrf52dk.This was stated by you only sir.That's I want clarity that is nrf52 dk support 3 wire interface or not ,because my slave module AD9837 works 3 wire spi interface only. devzone.nordicsemi.com/.../

RE: is nrf52 dk support 3 wire spi interface

RK — Mon, 29 May 2017 10:34:38 GMT

Then just don't connect the pin and use the same code. There is nothing special about SPI with just one pin unused. You can use the same code, you can even set it to use a pin for MISO and just don't connect that pin. The same example works.

RE: is nrf52 dk support 3 wire spi interface

pawan_v61 — Mon, 29 May 2017 10:32:54 GMT

i am connecting 3 wire(Sclk,ssn,MOSI pins only) & i am not connecting miso pin but it does not works well.can you please give me any example code for 3 wire connection interface & it is a simplex version not a half duplex version.

RE: is nrf52 dk support 3 wire spi interface

RK — Mon, 29 May 2017 07:56:56 GMT

Your description in your original question was just that you aren't using the MISO pin. That's absolutely fine. However now I wonder whether you didn't explain yourself properly and you're actually talking about the half-duplex version of SPI which uses one pin for MISO and for MOSI. That isn't supported. You can work around that with some circuitry but it's not easy.

So what are you actually talking about here?

RE: is nrf52 dk support 3 wire spi interface

pawan_v61 — Mon, 29 May 2017 07:46:36 GMT

even-though it was not working well ,are you sure nrf52 dk supports 3 wire spi interface. can you please share any example code supported 3 wire interface.I have spi example code(nRF5_SDK_13-pca10040) but it not working well on 3 wire spi interface

RE: is nrf52 dk support 3 wire spi interface

RK — Sat, 27 May 2017 12:47:30 GMT

Yes it supports it. You just set the MISO pin to -1 and even if you don't and it uses a pin, you just ignore the data.