nRF52840 Dongle FATFS issue when SPIM and SPIS are configured at the same time

RE: nRF52840 Dongle FATFS issue when SPIM and SPIS are configured at the same time

Karl Ylvisaker — Wed, 24 Jun 2020 12:30:54 GMT

Hello again Bertalan,

[quote user="BLaszlo"]Thank you for the clarification on the about the drive strength modification.[/quote]

No problem at all, I am happy to help!

[quote user="BLaszlo"]Is it enough to only modify the strength of the SCK to high or should I do the same for the MISO/MOSI (just asking because in the SPIM driver only the SCK is set up with NRF_GPIO_PIN_S0S1).[/quote]

I guess this depends on your specific hardware and requirements. What is your reasoning for needing this - are you seeing unusual signal waveforms on an oscilloscope, or does your SPI slave demand it in their specification? Could you also tell me what frequency you are intending to use? High drive might be favorable on higher speeds, since you typically get faster rise / fall times.

[quote user="BLaszlo"]For the paralell Dongle and DK development I usually branch the current example project, and while using the same main.c file the project file is different (it has the same structure as you have used for the examples so next to the main.c file we have the pca10056 and pca10059 folders containing the project file along with the compiled files too). I modified the project so far based on this guide[/quote]

Great, this is a good way of doing it.
I just had to make sure that you had accounted for the change in your project files, thank you for verifying this for me.

[quote user="BLaszlo"]So far everything was working the same way (ESB and SPIS), and this is the first behaviour that works differently, that is why I wrote the question here :)[/quote]

I understand. Good call! Could you connect the dongle to the debugger on the DK to use the debugger to identify the issue the dongle is facing? You will need to follow the "Using an external debugger" section of the Dongle Programming Tutorial also.
Alternatively, could you elaborate on what you are seeing with the dongle - do you know where it fails, and what do you mean specifically when you say that it does not work on the dongle?

Looking forward to solving this issue together,

Best regards,
Karl

RE: nRF52840 Dongle FATFS issue when SPIM and SPIS are configured at the same time

BLaszlo — Wed, 24 Jun 2020 11:44:26 GMT

Hello Karl,

Thank you for the clarification on the about the drive strength modification. Is it enough to only modify the strength of the SCK to high or should I do the same for the MISO/MOSI (just asking because in the SPIM driver only the SCK is set up with NRF_GPIO_PIN_S0S1).

For the paralell Dongle and DK development I usually branch the current example project, and while using the same main.c file the project file is different (it has the same structure as you have used for the examples so next to the main.c file we have the pca10056 and pca10059 folders containing the project file along with the compiled files too). I modified the project so far based on this guide: https://devzone.nordicsemi.com/nordic/short-range-guides/b/getting-started/posts/nrf52840-dongle-programming-tutorial (Adapting SDK projects for the nRF52840 Dongle paragraph)

So far everything was working the same way (ESB and SPIS), and this is the first behaviour that works differently, that is why I wrote the question here :)

Thank you again and best regards,

Bertalan

RE: nRF52840 Dongle FATFS issue when SPIM and SPIS are configured at the same time

Karl Ylvisaker — Wed, 24 Jun 2020 10:41:56 GMT

Hello Bertalan,

I am happy to hear that your software now works as expected!

[quote user="BLaszlo"]With this configuration my software (the SD card initalization is the same as the fatfs example so to validate it should be fine) works as expected, however I don't know if I should enable any configuration if I want to use these pins for SPI with high drive. Or now that it is connected to the pins with high frequency it works in a high drive mode automatically?[/quote]

The standard configuration by the SPIM driver is to set the drive strength to NRF_GPIO_PIN_S0S1.
You may change the drive strength by calling nrf_gpio_cfg after nrfx_spim_init has finished the SPIM setup.

[quote user="BLaszlo"]Still the original question why the SD card is working on the DK and not on the Dongle (same software and pin layout) is a mystery :)[/quote]

Are you running exactly the same project, or have you made sure to change the board file when generating the .hex for the dongle?
The nRF52840 dongle is PCA10059, while the nRF52840 DK is PCA10056.

Best regards,
Karl

RE: nRF52840 Dongle FATFS issue when SPIM and SPIS are configured at the same time

BLaszlo — Wed, 24 Jun 2020 10:20:57 GMT

Hello Karl,

Thank you for your response. Yes I am currently using the DK and a few hours ago I found a pin configuration that only consists of high frequency pins:

SCK: P0.11
MOSI: P0.13
MISO: P0.15
CS: P0.14

With this configuration my software (the SD card initalization is the same as the fatfs example so to validate it should be fine) works as expected, however I don't know if I should enable any configuration if I want to use these pins for SPI with high drive. Or now that it is connected to the pins with high frequency it works in a high drive mode automatically?

I know that the Dongle is a great tool for developing, I started to work with it in the beginning, but after a while I needed the debugger functionality on the DK so I switched to it. Still the original question why the SD card is working on the DK and not on the Dongle (same software and pin layout) is a mystery :)

Best regards,

Bertalan

RE: nRF52840 Dongle FATFS issue when SPIM and SPIS are configured at the same time

Karl Ylvisaker — Wed, 24 Jun 2020 09:32:40 GMT

Hello Bertalan,

Are you currently working on your DK, as suggested by Simon?
The pins you have selected - p.020 to p.023 - is already in use for the QSPI ( external memory ) on the DK. In order to use those pins as GPIO's you would have to cut and short the SolderBridges mentioned in the documentation.
You mention that you have tried several other pins, but none of the configurations have worked. Could you elaborate which configurations you have tried?

When you say that it did not work at all, are you testing the pin configurations with the fatfs example? I suggest using it as a base when changing the configuration, since you were able to verify that the example worked as expected earlier - this will make tracking and identifying issues much easier.

As Simon mentions, the dongle is a great companion when developing BLE applications - but it is usually best to start the development on the DK, since it has an onboard debugger and a much more broad connection interface.

Best regards,
Karl

RE: nRF52840 Dongle FATFS issue when SPIM and SPIS are configured at the same time

BLaszlo — Tue, 23 Jun 2020 10:30:21 GMT

Hello Simon,

I started to test the high drive GPIOs, but I might be missing some configuration because if I reconfigure the pin connections of the micro SD extension it does not work at all. I configured the following pins:

SCK: P0.20
MOSI: P0.21
MISO: P0.22
CS: P0.23

I also tested several other high drive pins, but neither of them now working as expected. The HFCLK is started when I initialize the used clocks.

I saw that the SPIM driver has the following configuration:

nrf_gpio_cfg(p_config->sck_pin,

NRF_GPIO_PIN_DIR_OUTPUT,

NRF_GPIO_PIN_INPUT_CONNECT,

NRF_GPIO_PIN_NOPULL,

NRF_GPIO_PIN_S0S1,

NRF_GPIO_PIN_NOSENSE);

Should I modify the 5th parameter to NRF_GPIO_PIN_H0H1 in order to make it work?

Also thank you for the suggestion of soldering a 2x5 pin connector on the Dongle, I will definitely try it later to troubleshoot the issue further.

Thank you in advance for your answer.

Br,

Bertalan

RE: nRF52840 Dongle FATFS issue when SPIM and SPIS are configured at the same time

Simonr — Mon, 22 Jun 2020 11:36:48 GMT

Yes, it should absolutely be possible to use SPIS, SPIM, and the radio simultaneously. Just remember to have the SPIS and SPIM in different instances so they don't conflict with one another.

I would suggest starting with your DK to find suitable GPIOs for the SPIS and SPIM, as there are way more GPIOs available there. Here is a list of GPIOs that can be used in high drive/frequency mode without interfering with radio performance:

P0.04
P0.05
P0.06
P0.07
P0.08
P0.11
P0.12
P0.13
P0.14
P0.15
P0.16
P0.17
P0.18 (configurable as pin reset as well)
P0.19
P0.20
P0.21
P0.22
P0.23
P0.24
P0.25
P1.00
P1.08
P1.09

Regarding debugging on the Dongle, you should be able to do so by soldering a 10-pin header onto the P1 header footprint on the bottom side of the Dongle (see section 6.3.2 in the Dongle user guide or the Dongle programming tutorial for details).

Best regards,

Simon

RE: nRF52840 Dongle FATFS issue when SPIM and SPIS are configured at the same time

BLaszlo — Mon, 22 Jun 2020 06:06:58 GMT

Hello Simon,

Thank you for your answer, and actually it is good that you mentioned the radio performance interference because it is used too (however at the point where it fails the radio is just initialized).

My first guess was the faulty connection, but this was proven wrong by writing to an older 16Gb micro SD card without any problem.

Is it possible to have an SPIS and SPIM interface, along with the radio? And if yes, in the future we might decide to embed an nRF52840 based chip on a PCB where we are not limited to the Dongle pins. Is there any suggestion which pin configuration would be the most efficient in this case?

In the meantime I will try to find out the error code for the disk initialization failure for the Dongle, but without a debugger environment it is quite challenging.

Thank you again and best regards,

Bertalan

RE: nRF52840 Dongle FATFS issue when SPIM and SPIS are configured at the same time

Simonr — Fri, 19 Jun 2020 13:48:59 GMT

The following pins that you mention are only recommended to use as standard drive and low frequency I/Os while the radio is being used.

P0.31
P0.02
P1.10
P1.15
P1.13
P0.29

This is because they may interfere with the radio's performance if running at high frequencies. This should not be an issue if you're not using the radio though, I just thought I should mention it.

This seems very strange, as none of those pins should conflict with anything but the radio in both the DK and Dongle. Are you positive that all the pins are attached to the Dongle properly? One thing though. According to the FatFs documentation, it is limited to 4GB sizes, so that might be the issue, although that doesn't explain why it works on the DK and not the Dongle. A disk init failure from the SD card reader leads me to think that the SD card reader isn't properly connected to the Dongle. Are you able to provide any error code of some sort if you try debugging?

Best regards,

Simon