Basic SPI reads and writes

[RodWatt]

Hi,

I have a SPI peripheral connected to the nRF960 DK. In order to access this correctly, I need to be able to write a byte to a specific address first and then read back from specific addresses. 

I can run the basic SPI example

https://github.com/Rallare/fw-nrfconnect-nrf/tree/nrf9160_samples/samples/nrf9160/spi

which carries out a basic loop back. This all works fine but I can't see how to write a specific byte to a specific address or read a specific address.

So, ideally I would like to write 0xD2 to address 0x80, wait 1 second and then read data from address 0x00.

Can you point me to a simple example please?

Ta,
Rod

[Øyvind]

Hello Rod, 

The SPI example you are using is the only one we have at the moment. The example is using the built-in SPI functions of the Zephyr project, perhaps you are able to find what you are looking for in the Zephyr samples? Also, have a look at the Zephyr SPI API and the SPI header file.

Ref. similar answer given by my colleague Jan Tore here. 

Kind regards,
Øyvind

[RodWatt]

Hi Øyvind,

I went back to the reply from Jan Tore on the ticket here. I realised that the BME280 has both an I2C and an SPI interface. So, I thought if I can get this sensor working over SPI and I can then try and migrate it to my own SPI sensor.

I have successfully connected and ran the BME280 sensor over I2C. I am now trying to access this over SPI. 

Im using the sample given here, 

https://github.com/zephyrproject-rtos/zephyr/blob/master/samples/sensor/bme280/src/main.c

I have set up SPI in my overlay file as suggested by Jan in the other ticket.

/*
 *
 * Copyright (c) 2018 Linaro Limited
 *
 * SPDX-License-Identifier: Apache-2.0
 */


&i2c2 {
        status = "ok";
        sda-pin = <1>;
        scl-pin = <0>;
        clock-frequency = <I2C_BITRATE_FAST>;
        };

&spi3 {
        status = "ok";
	sck-pin = <10>;
	mosi-pin = <11>;
	miso-pin = <12>;
	ss-pin = <13>;
	spi-max-frequency = <8000000>;
	bme280@0 {
		compatible = "bosch,bme280";
		reg = <0>;
		spi-max-frequency = <8000000>;
		label = "BME280";
	};

};

and also I have enabled SPI in my conf file

CONFIG_CONSOLE_SUBSYS=y
CONFIG_CONSOLE_GETCHAR=y
CONFIG_GPIO=y
CONFIG_STDOUT_CONSOLE=y

CONFIG_SERIAL=y
CONFIG_STDOUT_CONSOLE=y
CONFIG_UART_INTERRUPT_DRIVEN=y
CONFIG_TEST_RANDOM_GENERATOR=y

CONFIG_I2C=y
CONFIG_SENSOR=y

CONFIG_NET_BUF_USER_DATA_SIZE=1

CONFIG_LOG=n
CONFIG_LOG_DEFAULT_LEVEL=4
CONFIG_HEAP_MEM_POOL_SIZE=1024
CONFIG_MAIN_STACK_SIZE=4096
CONFIG_NEWLIB_LIBC=y

# SPI
CONFIG_SPI=y
CONFIG_SPI_3=y
CONFIG_SPI_3_NRF_SPIM=y
CONFIG_BME280=y
CONFIG_SPI_NRFX=y

However, I get an error

Secure Boot: MSP_NS 200216b0

Secure Boot: prepare to jump to Non-Secure image

***** Booting Zephyr OS v1.13.99-ncs1-5561-gde69d2df908f *****

Exception occurred in Secure State

***** HARD FAULT *****

  Fault escalation (see below)

***** BUS FAULT *****

  Precise data bus error

  BFAR Address: 0x50008120

***** Hardware exception *****

Current thread ID = 0x20020154

Faulting instruction address = 0x41f98

Fatal fault in ISR! Spinning...

Any thoughts?

[RodWatt]

Hi Øyvind,

Ok, I have gone though your steps as above.

1. I deleted CmakeCache.txt and ran zephyr-env.sh. When I tried to build, I get the same error as above.

2. I tried a complete new install. But as you will see from below, I still get the "West already initialised" error

Watts-MacBook-Pro:zephyrproject Watt$ mkdir NCS2
Watts-MacBook-Pro:zephyrproject Watt$ cd NCS2
Watts-MacBook-Pro:NCS2 Watt$ west init -m https://github.com/NordicPlayground/fw-nrfconnect-nrf --mr v0.4.0
West already initialized. Aborting.
Watts-MacBook-Pro:NCS2 Watt$ 

3. I don't think its my code, to prove this I tried to build at_client. I get the same error

Watts-MacBook-Pro:nrf9160 Watt$ cd at_client/
Watts-MacBook-Pro:at_client Watt$ ls
CMakeLists.txt	prj.conf	sample.yaml	src
Watts-MacBook-Pro:at_client Watt$ mkdir build
Watts-MacBook-Pro:at_client Watt$ cd build/
Watts-MacBook-Pro:build Watt$ cmake -GNinja -DBOARD=nrf9160_pca10090ns ..
-- Using application from '/Users/Watt/zephyrproject/ncs/nrf/samples/nrf9160/at_client'
Zephyr version: 1.14.99
-- Found PythonInterp: /usr/local/bin/python3 (found suitable version "3.7.3", minimum required is "3.4") 
-- Selected BOARD nrf9160_pca10090ns
-- Found west: /usr/local/bin/west (found suitable version "0.5.8", minimum required is "0.5.6")
-- Cache files will be written to: /Users/Watt/Library/Caches/zephyr
-- Loading /Users/Watt/zephyrproject/ncs/zephyr/boards/arm/nrf9160_pca10090/nrf9160_pca10090ns.dts as base
-- Overlaying /Users/Watt/zephyrproject/ncs/zephyr/dts/common/common.dts
nrf9160_pca10090ns.dts.pre.tmp:258.19-264.3: Warning (unique_unit_address_if_enabled): /soc/peripheral@40000000/clock@5000: duplicate unit-address (also used in node /soc/peripheral@40000000/power@5000)
Parsing Kconfig tree in /Users/Watt/zephyrproject/ncs/zephyr/Kconfig
Loading /Users/Watt/zephyrproject/ncs/zephyr/boards/arm/nrf9160_pca10090/nrf9160_pca10090ns_defconfig as base
Merging /Users/Watt/zephyrproject/ncs/nrf/samples/nrf9160/at_client/prj.conf
Configuration written to '/Users/Watt/zephyrproject/ncs/nrf/samples/nrf9160/at_client/build/zephyr/.config'
-- The C compiler identification is GNU 7.3.1
-- The CXX compiler identification is GNU 7.3.1
-- The ASM compiler identification is GNU
-- Found assembler: /Users/Watt/gnuarmemb/bin/arm-none-eabi-gcc
-- Performing Test toolchain_is_ok
-- Performing Test toolchain_is_ok - Success
Including module: nrf in path: /Users/Watt/zephyrproject/ncs/nrf
-- Using application from '/Users/Watt/zephyrproject/ncs/nrf/samples/nrf9160/spm'
Zephyr version: 1.14.99
Changed board to secure nrf9160_pca10090 (NOT NS)
-- Loading /Users/Watt/zephyrproject/ncs/zephyr/boards/arm/nrf9160_pca10090/nrf9160_pca10090.dts as base
-- Overlaying /Users/Watt/zephyrproject/ncs/zephyr/dts/common/common.dts
-- Overlaying /Users/Watt/zephyrproject/ncs/nrf/samples/nrf9160/spm/nrf9160_pca10090.overlay
nrf9160_pca10090.dts.pre.tmp:120.18-126.3: Warning (unique_unit_address_if_enabled): /soc/peripheral@50000000/uart@a000: duplicate unit-address (also used in node /soc/peripheral@50000000/i2c@a000)
  also defined at nrf9160_pca10090.dts.pre.tmp:512.8-514.3
nrf9160_pca10090.dts.pre.tmp:260.19-266.3: Warning (unique_unit_address_if_enabled): /soc/peripheral@50000000/clock@5000: duplicate unit-address (also used in node /soc/peripheral@50000000/power@5000)
Parsing Kconfig tree in /Users/Watt/zephyrproject/ncs/zephyr/Kconfig
Loading /Users/Watt/zephyrproject/ncs/zephyr/boards/arm/nrf9160_pca10090/nrf9160_pca10090_defconfig as base
Merging /Users/Watt/zephyrproject/ncs/nrf/samples/nrf9160/spm/prj.conf
Configuration written to '/Users/Watt/zephyrproject/ncs/nrf/samples/nrf9160/at_client/build/spm/zephyr/.config'
Including module: nrf in path: /Users/Watt/zephyrproject/ncs/nrf
Including module: mcuboot in path: /Users/Watt/zephyrproject/ncs/mcuboot/zephyr
Including module: tinycbor in path: /Users/Watt/zephyrproject/ncs/modules/lib/tinycbor
Including module: nrfxlib in path: /Users/Watt/zephyrproject/ncs/nrfxlib
Including module: mcuboot in path: /Users/Watt/zephyrproject/ncs/mcuboot/zephyr
Including module: tinycbor in path: /Users/Watt/zephyrproject/ncs/modules/lib/tinycbor
Including module: nrfxlib in path: /Users/Watt/zephyrproject/ncs/nrfxlib
CMake Warning at /Users/Watt/zephyrproject/ncs/zephyr/CMakeLists.txt:1523 (message):
  

        ------------------------------------------------------------
        --- WARNING:  __ASSERT() statements are globally ENABLED ---
        --- The kernel will run more slowly and use more memory  ---
        ------------------------------------------------------------


-- Configuring done
CMake Error at /Users/Watt/zephyrproject/ncs/zephyr/cmake/extensions.cmake:423 (add_library):
  Cannot find source file:

    src/main.c

  Tried extensions .c .C .c++ .cc .cpp .cxx .cu .m .M .mm .h .hh .h++ .hm
  .hpp .hxx .in .txx
Call Stack (most recent call first):
  /Users/Watt/zephyrproject/ncs/zephyr/cmake/app/boilerplate.cmake:554 (zephyr_library_named)
  ../spm/CMakeLists.txt:3 (include)


CMake Error at /Users/Watt/zephyrproject/ncs/zephyr/cmake/extensions.cmake:423 (add_library):
  No SOURCES given to target: spm_app
Call Stack (most recent call first):
  /Users/Watt/zephyrproject/ncs/zephyr/cmake/app/boilerplate.cmake:554 (zephyr_library_named)
  ../spm/CMakeLists.txt:3 (include)


-- Build files have been written to: /Users/Watt/zephyrproject/ncs/nrf/samples/nrf9160/at_client/build
Watts-MacBook-Pro:build Watt$ 

So, I think i need to carry out a complete reinstall but it won't seem to let me do this simply my creating a new NCS2 directory. 

How can I do a clean install?

Rod

[Øyvind]

Hi Rod, 

Really sorry for this being so difficult to fix, I have not seen similar issues. 

RodWatt said:

2. I tried a complete new install. But as you will see from below, I still get the "West already initialised" error

 You need to find a folder named .west on your computer. This folder is generated when initializing west. Try to find this folder and delete it to see if this has any impact.

I am discussing the issue in my team and will get back to you asap.

Kind regards,
Øyvind

[RodWatt]

Hi Øyvind,

I got this working but not 100% sure what actually did the trick. Based on this thread "

nRF9160 at_client sample project"

i deleted my path and env variables.

I then ran this again..

pip3 install -r zephyr/scripts/requirements.txt
pip3 install -r nrf/scripts/requirements.txt
pip3 install -r mcuboot/scripts/requirements.txt

as well as the update as above. Something did the trick and it burst into life.

So,  I can no generate a merged.hex file and my code complies and runs. Unfortunately, my basic SPI reads and writes still dont work but at least I am now running on SPM

Rod

[Øyvind]

Really glad to hear that it solved the issue!

-Øyvind

[RodWatt]

Yes, it solved the SPM issue, but Im now back to the problem of trying to get SPI to work!

[Øyvind]

Ok. Just to get back on the right track again:

• Are you able to run the SPI example without BME280? What problems are you seeing?
• Is the hard fault issue still there?
  • In prj.conf, you must add:
    

    CONFIG_MAIN_STACK_SIZE=4096

Kind regards,
Øyvind

[RodWatt]

Hi,

I managed to get it working !

Thanks,

Rod

[paul_tanner]

Hi Rod,

I'm travelling the same route on nrfConnect SDK 1.4

Like you I got my I2C version working first and then wanted to use SPI.

Any chance you could share your working sample?

I have also posted this https://devzone.nordicsemi.com/f/nordic-q-a/70393/nrf9160-dk-spi-from-bme280-sensor-config-issue - no answer on that so far.

Thx.

Regards, Paul

[RodWatt]

Hi Paul,

I have not looked at this for a while so I can't say 100% that this code is correct, but I have shared it anyway. Let me know if it works and if not, I will do a bit more digging my end.

&spi3 {
        status = "ok";
	sck-pin = <10>;
	mosi-pin = <11>;
	miso-pin = <12>;
	ss-pin = <13>;
	spi-max-frequency = <4000000>;
	bme280@76 {
		compatible = "bosch,bme280";
		reg = <0x76>;
		spi-max-frequency = <4000000>;
		label = "BME280";
	};

};

CONFIG_CONSOLE_SUBSYS=y
CONFIG_CONSOLE_GETCHAR=y
CONFIG_GPIO=y
CONFIG_STDOUT_CONSOLE=y

CONFIG_SERIAL=y
CONFIG_STDOUT_CONSOLE=y
CONFIG_UART_INTERRUPT_DRIVEN=y
CONFIG_TEST_RANDOM_GENERATOR=y

CONFIG_SENSOR=y

CONFIG_NET_BUF_USER_DATA_SIZE=1

CONFIG_LOG=y
CONFIG_LOG_DEFAULT_LEVEL=4
CONFIG_HEAP_MEM_POOL_SIZE=1024
CONFIG_MAIN_STACK_SIZE=4096
CONFIG_NEWLIB_LIBC=y

# SPI
CONFIG_SPI=y
CONFIG_SPI_3=y
CONFIG_SPI_3_NRF_SPIM=y
CONFIG_BME280=y
CONFIG_SPI_NRFX=y
CONFIG_SENSOR_LOG_LEVEL_WRN=y

CONFIG_TRUSTED_EXECUTION_NONSECURE=y

#include <zephyr.h>
#include <device.h>
#include <sensor.h>
#include <stdio.h>

#undef DT_BOSCH_BME280_BUS_I2C
#define DT_BOSCH_BME280_BUS_SPI

void main(void)
{

int i;
	printf("Boiler Guardian Test Code - BME280 over SPI \n");
	printf(" \n");

	struct device *dev = device_get_binding("BME280");

	printf("dev %p name %s\n", dev, dev->config->name);

	printf("Boiler Guardian Test Code - BME280 - got binding  \n");
	printf(" \n");

	for(i = 1; i < 2; i++) {
		struct sensor_value temp, press, humidity;

		sensor_sample_fetch(dev);
		sensor_channel_get(dev, SENSOR_CHAN_AMBIENT_TEMP, &temp);
		sensor_channel_get(dev, SENSOR_CHAN_PRESS, &press);
		sensor_channel_get(dev, SENSOR_CHAN_HUMIDITY, &humidity);


		printf("Environmental Temperature: %d.%d Degrees Cent. \n", temp.val1, temp.val2);
		printf("Environmental Pressure: %d.%02d Bar \n", press.val1, press.val2);
		printf("Environmental Humidity: %d.%02d per/cent \n", humidity.val1, humidity.val2);


	}
}

[paul_tanner]

Many thanks Rod.

Things have moved on a lot but this was very helpful in getting me unstuck.

With a bit of help from Simon this is now sorted out.

devzone.nordicsemi.com/.../290233

Regards, Paul