flashwrite persistence

[paul_tanner]

Using sdk12.3 on pca10040.

I wanted to test persistence so I modified the example from the SDK as follows:  log what's already there.  don't erase.  enter new data.  log it again.

Using the provided example /peripheral/flashwrite to get the starting address

pg_size = NRF_FICR->CODEPAGESIZE;
pg_num = NRF_FICR->CODESIZE - 1; // Use last page in flash
addr = (uint32_t *)(pg_size * pg_num);

I then say:

flash_word_write(addr, (uint32_t)patwr);
NRF_LOG_INFO("'%c' was written to flash at %08x\r\n", patwr, (unsigned long) addr);
patrd = (uint8_t)*addr;
NRF_LOG_INFO("'%c' %08x was read from flash at %08x\r\n\r\n", patrd, *addr, (unsigned long) addr);

Regardless of the value of patwr (a character from the console) written to 0007F000 the read value is 00000000.

(So the fact that it does not persist across a reset is not surprising.)

Causes could be that the address is wrong or that writing to flash is somehow being blocked.

Any suggestions pls.

[paul_tanner]

Sorry, something I did not try was to re-instate the call to flash_page_erase(addr);

That makes the sketch work but of course this prevents it from persisting across a reset.

[Edvin]

Hello,

The flash works in the way that you can only flip bits from 1 to 0. In order to flip them back to 1, you need to delete the entire flash page, unfortunately. This means that you need to somehow work around this, by figuring out where your latest data is written. 

One way to work around this is to use the FDS module, which stores records with record IDs, which you can use to update a record, delete records, or write new records. 

You can check out the guide in or documentation on how to use the FDS module.

So there you would typically use functions like fds_record_write(), fds_record_delete(), fds_record_update(), and so on. The FDS module will also evenly distribute the flash tear, so it will ensure maximum durance for the flash.

Best regards,

Edvin

[paul_tanner]

OK Thx Edvin.  I guess I saw flashwrite and not fds in the 12.3 examples and jumped to a conclusion. :-(

I see that 12.3 does include the fds library so I made an example using the document you mention.

The example talks about softdevice but I assume it should work without one.

The first error I get is

../../../main.c:77:18: error: initializer element is not constant

ret_code_t ret = fds_register(fds_evt_handler);

                  ^

.. which seems odd.  Is this code viable in 12.3 with the 12.3 fds library?

Thx.

[Edvin]

What IDE are you using?

[paul_tanner]

straight armgcc

[Edvin]

Hello,

The fds module should work without the softdevice as well. Just make sure to include the correct fstorage files (that are used by the fds files). 

There are two fstorage.c files. One called fstorage.c, and one called fstorage_nosd.c (no softdevice). Use the last one.

Your compiler error, "initializer element is not constant" is probably because you are trying to add 

ret_code_t ret = fds_register(fds_evt_handler);

outside a function.

These instructions can't be copy-pasted into a main.c file. You must have all function calls inside a function, e.g. your main() function, or another function that you create. Something like this:

static void fds_evt_handler(fds_evt_t const * p_fds_evt)
{
    switch(p_fds_evt->id)
    {
        case FDS_EVT_INIT:
            if(p_fds_evt->result != FDS_SUCCESS)
            {
                // initialization failed.
            }
            break;
        
        default:
            break;
    }
}

void my_fds_init_function(void)
{
    ret_code_t ret = fds_register(fds_evt_handler);
    if(ret != FDS_SUCCESS)
    {
        //registering failed. 
    }
    ret = fds_init();
    if(ret != FDS_SUCCESS)
    {
        // Handle error.
    }
}

BR,

Edvin

[paul_tanner]

Thx Edvin and apologies for forgetting the main()

Now when I try to build this as above I find that  fds_record_t  is undefined.

I think I have the right stuff in the attached Makefile.

Again, I'm wondering if I can do this on SDK 12.3?

Thx. Paul

Fullscreen 8308.Makefile.txt Download

PROJECT_NAME     := flashwrite_pca10040
TARGETS          := nrf52832_xxaa
OUTPUT_DIRECTORY := _build

SDK_ROOT := ../../../../../..
PROJ_DIR := ../../..

$(OUTPUT_DIRECTORY)/nrf52832_xxaa.out: \
  LINKER_SCRIPT  := flashwrite_gcc_nrf52.ld

# Source files common to all targets
SRC_FILES += \
  $(SDK_ROOT)/components/libraries/log/src/nrf_log_backend_serial.c \
  $(SDK_ROOT)/components/libraries/log/src/nrf_log_frontend.c \
  $(SDK_ROOT)/components/libraries/util/app_error.c \
  $(SDK_ROOT)/components/libraries/util/app_error_weak.c \
  $(SDK_ROOT)/components/libraries/util/app_util_platform.c \
  $(SDK_ROOT)/components/libraries/util/nrf_assert.c \
  $(SDK_ROOT)/components/libraries/util/sdk_errors.c \
  $(SDK_ROOT)/components/libraries/fds/fds.c \
  $(SDK_ROOT)/components/libraries/fstorage/fstorage_nosd.c \
  $(SDK_ROOT)/components/boards/boards.c \
  $(SDK_ROOT)/components/drivers_nrf/common/nrf_drv_common.c \
  $(SDK_ROOT)/components/drivers_nrf/uart/nrf_drv_uart.c \
  $(PROJ_DIR)/main.c \
  $(SDK_ROOT)/external/segger_rtt/RTT_Syscalls_GCC.c \
  $(SDK_ROOT)/external/segger_rtt/SEGGER_RTT.c \
  $(SDK_ROOT)/external/segger_rtt/SEGGER_RTT_printf.c \
  $(SDK_ROOT)/components/toolchain/gcc/gcc_startup_nrf52.S \
  $(SDK_ROOT)/components/toolchain/system_nrf52.c \

# Include folders common to all targets
INC_FOLDERS += \
  $(SDK_ROOT)/components \
  $(SDK_ROOT)/components/libraries/util \
  $(SDK_ROOT)/components/toolchain/gcc \
  $(SDK_ROOT)/components/drivers_nrf/uart \
  ../config \
  $(SDK_ROOT)/components/drivers_nrf/common \
  $(PROJ_DIR) \
  $(SDK_ROOT)/external/segger_rtt \
  $(SDK_ROOT)/components/libraries/bsp \
  $(SDK_ROOT)/components/libraries/fds \
  $(SDK_ROOT)/components/libraries/fstorage \
  $(SDK_ROOT)/components/libraries/experimental_section_vars \
  $(SDK_ROOT)/components/drivers_nrf/nrf_soc_nosd \
  $(SDK_ROOT)/components/toolchain \
  $(SDK_ROOT)/components/device \
  $(SDK_ROOT)/components/libraries/log \
  $(SDK_ROOT)/components/boards \
  $(SDK_ROOT)/components/drivers_nrf/delay \
  $(SDK_ROOT)/components/toolchain/cmsis/include \
  $(SDK_ROOT)/components/drivers_nrf/hal \
  $(SDK_ROOT)/components/libraries/log/src \

# Libraries common to all targets
LIB_FILES += \

# C flags common to all targets
CFLAGS += -DNRF52_PAN_12
CFLAGS += -DNRF52_PAN_15
CFLAGS += -DNRF52_PAN_58
CFLAGS += -DNRF52_PAN_20
CFLAGS += -DNRF52_PAN_54
CFLAGS += -DNRF52
CFLAGS += -DNRF52_PAN_51
CFLAGS += -DNRF52_PAN_36
CFLAGS += -DCONFIG_GPIO_AS_PINRESET
CFLAGS += -DNRF52_PAN_64
CFLAGS += -DNRF52_PAN_55
CFLAGS += -DBOARD_PCA10040
CFLAGS += -DNRF52_PAN_31
CFLAGS += -DNRF52832
CFLAGS += -DBSP_DEFINES_ONLY
CFLAGS += -mcpu=cortex-m4
CFLAGS += -mthumb -mabi=aapcs
CFLAGS +=  -Wall -Werror -O3 -g3
CFLAGS += -mfloat-abi=hard -mfpu=fpv4-sp-d16
# keep every function in separate section, this allows linker to discard unused ones
CFLAGS += -ffunction-sections -fdata-sections -fno-strict-aliasing
CFLAGS += -fno-builtin --short-enums 

# C++ flags common to all targets
CXXFLAGS += \

# Assembler flags common to all targets
ASMFLAGS += -x assembler-with-cpp
ASMFLAGS += -DNRF52_PAN_12
ASMFLAGS += -DNRF52_PAN_15
ASMFLAGS += -DNRF52_PAN_58
ASMFLAGS += -DNRF52_PAN_20
ASMFLAGS += -DNRF52_PAN_54
ASMFLAGS += -DNRF52
ASMFLAGS += -DNRF52_PAN_51
ASMFLAGS += -DNRF52_PAN_36
ASMFLAGS += -DCONFIG_GPIO_AS_PINRESET
ASMFLAGS += -DNRF52_PAN_64
ASMFLAGS += -DNRF52_PAN_55
ASMFLAGS += -DBOARD_PCA10040
ASMFLAGS += -DNRF52_PAN_31
ASMFLAGS += -DNRF52832
ASMFLAGS += -DBSP_DEFINES_ONLY

# Linker flags
LDFLAGS += -mthumb -mabi=aapcs -L $(TEMPLATE_PATH) -T$(LINKER_SCRIPT)
LDFLAGS += -mcpu=cortex-m4
LDFLAGS += -mfloat-abi=hard -mfpu=fpv4-sp-d16
# let linker to dump unused sections
LDFLAGS += -Wl,--gc-sections
# use newlib in nano version
LDFLAGS += --specs=nano.specs -lc -lnosys


.PHONY: $(TARGETS) default all clean help flash 

# Default target - first one defined
default: nrf52832_xxaa

# Print all targets that can be built
help:
	@echo following targets are available:
	@echo 	nrf52832_xxaa

TEMPLATE_PATH := $(SDK_ROOT)/components/toolchain/gcc

include $(TEMPLATE_PATH)/Makefile.common

$(foreach target, $(TARGETS), $(call define_target, $(target)))

# Flash the program
flash: $(OUTPUT_DIRECTORY)/nrf52832_xxaa.hex
	@echo Flashing: $<
	nrfjprog --program $< -f nrf52 --sectorerase
	nrfjprog --reset -f nrf52

erase:
	nrfjprog --eraseall -f nrf52

[Edvin]

Hello Paul,

Yes. This is possible in SDK12.3.0

fds_record_t is defined in fds.h, so you must add the folder including this in your INC_FOLDERS in your makefile.

$(SDK_ROOT)/components/libraries/fds \

I see that you have included it in your makefile, but there must be something wrong with it. 

Do you intend to use the softdevice in your final appliaction?

Can you please paste the compiler output log?

BR,

Edvin

[paul_tanner]

Thx Edvin,

Initially without softdevice.  Will add that later.

Compiling file: main.c

../../../main.c: In function 'main':

../../../main.c:100:13: error: 'struct <anonymous>' has no member named 'p_data'

  record.data.p_data       = &m_deadbeef;

             ^

../../../main.c:101:13: error: 'struct <anonymous>' has no member named 'length_words'

  record.data.length_words = 1;   /* one word is four bytes. */

             ^

../../../main.c:110:13: error: 'struct <anonymous>' has no member named 'p_data'

  record.data.p_data       = &m_hello;

             ^

../../../main.c:112:13: error: 'struct <anonymous>' has no member named 'length_words'

  record.data.length_words = (sizeof(m_hello) + 3) / 4;

             ^

make: *** [_build/nrf52832_xxaa_main.c.o] Error 1

 

I may have misinterpreted the above?

Thx. Paul