Simple SPI

RE: Simple SPI

Håkon Alseth — Thu, 14 Jan 2021 11:33:21 GMT

Hi,

Glad to hear that you got everything working!

Kind regards,

Håkon

RE: Simple SPI

verulia — Thu, 14 Jan 2021 10:22:01 GMT

Hi Hakon,

I finally managed to solve the problem. I realized that I have to choose my sampling frequency as 25Mhz and I also connect the ground to a different gnd pin and now I am able to see the signals properly. Thank you for the help.

Best

RE: Simple SPI

Håkon Alseth — Thu, 07 Jan 2021 11:31:47 GMT

Hi,

[quote user="verulia"]Can you share the code that you tried and managed to scope the jedec id so that I can also try to see it on my analyzer too.It would be so helpful for my case.[/quote]

The changes I made are attached in the case you linked to. If you read the full case you linked to, the problem was a physical soldering issue on one board.

In your other case, it seems that the pins are indeed working, just that the sampling rate on your logic analyzer isn't set high enough to properly sample a 4 MHz signal:

https://devzone.nordicsemi.com/f/nordic-q-a/69363/reading-jedec-id-with-spi-on-nrf9160/285610#285610

Try swapping the pins in the overlay file, delete your build-folder, re-import the project in SES and build/flash it again.

Kind regards,

Håkon

RE: Simple SPI

verulia — Thu, 07 Jan 2021 11:07:19 GMT

Hi Hakan,

Unfortunately, this is what I am seeing with 10 Mhz.

Maybe I should try a different example. I searched other tickets and saw this

https://devzone.nordicsemi.com/f/nordic-q-a/64355/is-there-any-spi-example-of-ncs-v1-3-to-refer-to/262533#262533. In that post, you said that you were able to read the jedec id. I am also trying to communicate with an external flash and read its jedec id. Do you have the simple code for that project that you read the jedec id for w32q flash? Does reading the jedec id part work although I don't have the flash, is it still possible to scope the signal from logic analyzer? Can you share the code that you tried and managed to scope the jedec id so that I can also try to see it on my analyzer too.It would be so helpful for my case.

Thank you

RE: Simple SPI

Håkon Alseth — Thu, 07 Jan 2021 10:17:59 GMT

Hi,

I tested your .hex file in that .zip (the file build_nrf9160dk_nrf9160ns/zephyr/merged.hex):

The signal is 4MHz, so you should set the sampling rate > 8MHz on your logic analyzer.

Kind regards,

Håkon

RE: Simple SPI

verulia — Thu, 07 Jan 2021 10:07:09 GMT

Hi Hakan,

Yes sure.

devzone.nordicsemi.com/.../1033.simple_5F00_spi_5F00_test_5F00_nrf9160.zip

RE: Simple SPI

Håkon Alseth — Thu, 07 Jan 2021 10:00:19 GMT

Hi,

Can you please share your project?

Kind regards,

Håkon

RE: Simple SPI

verulia — Thu, 07 Jan 2021 09:56:03 GMT

Hi Hakan,

I already changed that it is 3V. Are you observing the clk signal without doing any triggering? Does it show up as long as you connect clk pin to logic analyzer? I didn't understand what I am doing wrong? Are my adjustmenst correct?

-MISO AND MOSI are connected on NRF

-Sampling freq=5Mhz(I also tried other ones no change)

-Only clk is connected to logic analyzer

- I am not doing any triggering currently but I tried all the triggering options nothing changed

Thank you

RE: Simple SPI

Håkon Alseth — Thu, 07 Jan 2021 09:35:38 GMT

Hi,

Are you able to test with 1.8V setting in your logic analyzer SW? If you're using the nRF9160-DK, its default setting is 1.8V (changeable to 3.0V via the VDD_IO switch near the power switch).

Kind regards,

Håkon

RE: Simple SPI

verulia — Thu, 07 Jan 2021 08:54:27 GMT

Also this is the output on lte link monitor when I connect MISO TO MOSI:

so it seems there aren't any problem in loopback test functionality.

RE: Simple SPI

verulia — Thu, 07 Jan 2021 08:51:48 GMT

Hi Hakan,

This is the output right now. MISO AND MOSI are connected together on the nrf. clk pin is 11. I only connected clk pin<11> to logic analyzer on CH2. My sampling rate is 1 MHz rigth now. When I increase the sampling rate I only see high(1) on CH2. The code that I am using is the one in the attachment I didn't change anything in that code. Once I get this observation work I will modifiy the code and move on. I am sure that logic analyzer is working because when I toggle the pins manually I can properly observe it. I was also be able to observe the clock signal with different microcontroller(nor nrf)

Thank you.

RE: Simple SPI

Håkon Alseth — Thu, 07 Jan 2021 08:33:54 GMT

Hi,

Yes, it seems to toggle at my end:

[quote user="verulia"]Can you see the clock output and the miso properly from the logic analyzer?[/quote]

MISO is the "master in, slave out", so unless you have anything externally connected to the device, it will not show anything. This is why I asked if you have connected the MISO signal to the MOSI signal. This is a loopback test.

Can you please confirm which pins aren't working, as per my former response?

Is it only the CLK pin not outputting a signal? Please provide a screenshot of your sampled signal.

Can you please share your current project so I can try it at my end?

Kind regards,

Håkon

RE: Simple SPI

verulia — Thu, 07 Jan 2021 08:06:15 GMT

Hi Hakan,

Thanks for the reply. This issue is kind of important for me hence I need to solve it. Did you try the code that you sent me "this simple spi loopback", with logic analyzer? Can you see the clock output and the miso properly from the logic analyzer? Seeing the spi functionality from logic analyzer is very important for me to move on in my project. Also if you are able to see it from logic analyzer can you tell me your settings in the system such as sampling freq etc.

Thank you for the help

RE: Simple SPI

Håkon Alseth — Thu, 10 Dec 2020 09:10:41 GMT

Hi,

[quote user="verulia"]Yes when I connect miso to mosi with a wire I receive the same value. I also changed the gpio pins for clk and miso it also works fine when I change them I can still see the outputs on lte link monitor. The only problem is I cant even see the clk ouput 1-0-1-0 on logic analyzer, I also cant see mosi.[/quote]

If you are not able to view the data on your logic analyzer when looking at MISO, but the serial output shows that it sends for instance 10 and receives 10 when you connect MISO to MOSI, then the pin itself does toggle.

It is then a problem with your logic analyzer PC setup.

Kind regards,

Håkon

RE: Simple SPI

verulia — Wed, 09 Dec 2020 17:13:58 GMT

Hi,

Yes when I connect miso to mosi with a wire I receive the same value. I also changed the gpio pins for clk and miso it also works fine when I change them I can still see the outputs on lte link monitor. The only problem is I cant even see the clk ouput 1-0-1-0 on logic analyzer, I also cant see mosi. The clk pin always gives 1 in logic analyzer but it should be 0-1-0-1. I changed the sampling rate, frequenct however still result is same. I didn't understand what I am missing. Should I have to make additional changes in the code or should I need to do some adjustments in the logic analyzer. But in logic analyzer when I just send 1-0-1-0 from gpio pins(different from spi pins) I was be able to see the output clearly without doing any modification

Thank you

RE: Simple SPI

Håkon Alseth — Wed, 09 Dec 2020 13:59:09 GMT

Hi,

On the UART terminal (serial terminal), are you getting the expected output when connecting MISO to MOSI using a patch wire?

ie:

TX sent: X

RX recv: X

BR,

Håkon

RE: Simple SPI

verulia — Wed, 09 Dec 2020 13:46:24 GMT

Hi, I couldn't get an answer for my last reply do you have any idea of what can I also try?

Thank for the help so much

RE: Simple SPI

verulia — Wed, 02 Dec 2020 08:39:59 GMT

Hi Hakan,

The pins are changed no problem in that part rigth now but still I can't see the rigth signal in the logic analyzer. I adjusted edge triggering with rising edge( also tried with falling and all other triggering options) I see that clk signal seems always high. Not 0-1-0-1 its always one.I played with sampling frequency but it also didn't change the result. I tested the logic analyzer with different chip and I saw 1-0-1-0 clk signal so logic analyzer is working fine. I didn't change the code that you sent me and it is doing loopback so no problem in spi functionality. Then what should I do in this case? I just want to see the clk signal and mosi in this case I thought that just attaching the logic analyzer to those output pins was sufficient to see the outputs am I missing something in this point?

Thank you

RE: Simple SPI

Håkon Alseth — Wed, 25 Nov 2020 11:57:19 GMT

You can use another gpio by setting the .overlay file.

For instance:

&spi3 {
	compatible = "nordic,nrf-spim";
	status = "okay";
	sck-pin = <x>;
	mosi-pin = <y>;
	miso-pin = <z>;
};

Where x, y, z are a valid and unused gpio. If it doesn't switch the gpios, try deleting your build folder and re-importing the project.

Kind regards,

Håkon

RE: Simple SPI

verulia — Tue, 24 Nov 2020 14:28:10 GMT

Hello,

I think I misunderstood the switching part because I just try to switch the pins of mosi and clk in the overlay file by just writing mosi<10> clk<11> however this doesn't work. How can I switch them what is the right way?

Thank you

RE: Simple SPI

verulia — Tue, 24 Nov 2020 12:40:44 GMT

I didn't do any triggering, I just connected one port to the ground and other port to clk output. As trial I triggered the output channel of clk port both risinf and falling but result didn't change.

RE: Simple SPI

Håkon Alseth — Tue, 24 Nov 2020 11:59:33 GMT

The sample doesn't send all the time (once per second), are you sure you're triggering on the correct channel, with the correct edge triggering?

RE: Simple SPI

verulia — Tue, 24 Nov 2020 10:58:54 GMT

Hi,

I tested the logic analyzer for testing other gpio pins and it working however I still can't see any signal from spi code. GND is connected and I can't see clock,miso and mosi. I reverse the pins for mosi and clk however I am always getting 1(high) from <10> port. I also tried to decrease the sampling rate but still I am always getting hi from <10> port even though the GND is not connected. I should be able to directly observe the clk signal from logic analyzer right without changing anything in the code?

Thank you

RE: Simple SPI

Håkon Alseth — Mon, 23 Nov 2020 13:52:35 GMT

Hi,

[quote user="verulia"]I can loopback which means spi is working but I can't see any signals from scana. [/quote]

So, when sending x, you receive x back as well? Then it seems that there's something wrong with your logic analyzer setup. Check the GND connection.

[quote user="verulia"]Also, if I wan't to change this gpio pin setting should I use gpio_pin_configure?[/quote]

Yes, you can use that to configure any unused GPIO if you'd like.

Kind regards,

Håkon

RE: Simple SPI

verulia — Mon, 23 Nov 2020 09:37:03 GMT

Hi,

I am using v1.4.0 SDK. In spi example I can't even see the MOSI signal in scana. I can loopback which means spi is working but I can't see any signals from scana. Also, if I wan't to change this gpio pin setting should I use gpio_pin_configure?

Thank you