continuous sampling stopped example: saadc_advanced_non_blocking_internal_timer

[ChrtistophAT]

Hello folks,

aim of my task is to transfer ADC data through USB from my nrf5340DK to my windows PC, so I can use this data to controll some python game.

SDK: nrf2.6.2

toolchain: v2.6.2

I evaluated the example "saadc_advanced_non_blocking_internal_timer" and changed the saadc_handler() function, especially the "case NRFX_SAADC_EVT_BUF_REQ:" , so its continuously sampling the ADC channel. Problem was, that 

[00:13:02.882,751] <inf> NRFX_EXAMPLE: 300

--- 76 messages dropped ---

[00:13:02.891,448] <inf> NRFX_EXAMPLE: 302

--- 76 messages dropped ---

[00:13:02.900,146] <inf> NRFX_EXAMPLE: 302

Messages were dropped, so I want to implement the

USB CDC ACM Sample Application example

USB CDC ACM Sample Application

its for the sdk v2.5.1, but without adjusting its running fine in my build v2.6.1.

The problem I encounter, when I adjust the prj.conf for the USB implementation like

#project configuration

CONFIG_GPIO=n

CONFIG_NRFX_GPIOTE0=y

CONFIG_NRFX_SAADC=y

#usb cobfiguration

CONFIG_USB_DEVICE_STACK=y            # Enables the USB device stack

# Sets the product name

CONFIG_USB_DEVICE_PRODUCT="Zephyr CDC ACM sample"

#ProductID the following line is not allowed to make comments after ID "Remove the Inline Comment"

CONFIG_USB_DEVICE_PID=0x0001    

CONFIG_SERIAL=y                      # Enables UART support

CONFIG_UART_INTERRUPT_DRIVEN=y       # Enables interrupt-driven UART (needed for USB CDC ACM)

CONFIG_UART_LINE_CTRL=y              # Enables line control for UART (needed for DTR detection)

#logging through zephyr

CONFIG_DEBUG=y               # Enable debug symbols

CONFIG_LOG_MODE_IMMEDIATE=y  # Ensure logs are flushed immediately for debugging.

CONFIG_LOG_BACKEND_UART=y    # Logs will output to UART or RTT (depends on your setup).

my familiar irq sequence for the SAADC sampling differes. I ad this image, so it easier to see

The last interrupt with event mask = 3, should be = 2 and I dont know why. Afterwards its executing the Saadc_event_handle() and the 

m_cb.buffer_secondary.p_buffer = 0x0 <_vector_table>

so it points to null.

I tried to increase the priority from the saadc to 2

nrfx_saadc_init(2);

My USB implementation works and I can see the device in the Settings - Bluetooth & other Devices properly. When I comment out the init from the USB in my main.c , still persists the error and not continuously sampling. 

When I comment out the added prj.conf configuration for the USB, its sampling continuously again.

Doese someone have any clue why this is happening?

Many thanks in advance,

Christoph 

 

[ChrtistophAT]

Here is something I encountered while investigating. The code commit is where I just code reviewed the example from saadc "saadc_advanced_non_blocking_internal_timer" . Despite that, there is already some USB configuration in the prj.conf . Could be that I already started implementation and commited afterwards the codereview status. Anyway the prj.conf is like:

#project configuration

CONFIG_GPIO=n

CONFIG_NRFX_GPIOTE0=y

CONFIG_NRFX_SAADC=y

CONFIG_LOG_BUFFER_SIZE=8192

CONFIG_NRFX_SAADC_LOG=y #log enable for saadc library

#config usb data transfer

CONFIG_USB_CDC_ACM=y

CONFIG_USB_DEVICE_STACK=y

CONFIG_USB_DEVICE_MANUFACTURER="Your Company Name"

CONFIG_USB_DEVICE_PRODUCT="Your Product Name"

CONFIG_USB_DEVICE_VID=0x1915

CONFIG_USB_DEVICE_PID=0x520F

CONFIG_UART_INTERRUPT_DRIVEN=y

CONFIG_UART_LINE_CTRL=y

and the code is untouched from the example, just some LOG_INF() and SAMPLING_ITERATIONS

The code samples as expected all the iterations and buffers. 

[00:00:00.436,370] <inf> NRFX_EXAMPLE: Starting nrfx_saadc advanced non-blocking sampling with internal timer example.
[00:00:00.447,448] <inf> NRFX_SAADC: Function: nrfx_saadc_init, error code: NRFX_SUCCESS.
[00:00:00.447,540] <inf> NRFX_EXAMPLE: GPIOTE status: initialized
[00:00:00.447,570] <inf> NRFX_EXAMPLE: SAADC calibration will be started.
[00:00:00.447,570] <inf> NRFX_SAADC: nrfx_saadc_offset_calibrate called
[00:00:00.447,570] <inf> NRFX_EXAMPLE: Calibration started successfully
[00:00:00.447,631] <inf> NRFX_EXAMPLE: SAADC event: CALIBRATEDONE
[00:00:00.447,662] <inf> NRFX_EXAMPLE: saadc_mode_trigger() will be called to start the sampling.
[00:00:00.447,662] <inf> NRFX_EXAMPLE: SAADC event: READY
[00:00:00.447,692] <inf> NRFX_EXAMPLE: SAADC event: BUF_REQ
[00:00:00.447,937] <inf> NRFX_SAADC: m_cb address: 0x20003a3c, buffer_secondary: 0x20002686
[00:00:00.447,967] <inf> NRFX_EXAMPLE: 274
[00:00:00.447,967] <inf> NRFX_EXAMPLE: 276
[00:00:00.447,967] <inf> NRFX_EXAMPLE: 273
[00:00:00.447,998] <inf> NRFX_EXAMPLE: SAADC event: BUF_REQ
[00:00:00.448,333] <inf> NRFX_SAADC: m_cb address: 0x20003a3c, buffer_secondary: 0x20002680
[00:00:00.448,333] <inf> NRFX_EXAMPLE: 273
[00:00:00.448,333] <inf> NRFX_EXAMPLE: 276
[00:00:00.448,364] <inf> NRFX_EXAMPLE: 275
[00:00:00.448,364] <inf> NRFX_EXAMPLE: SAADC event: BUF_REQ
[00:00:00.448,699] <inf> NRFX_SAADC: m_cb address: 0x20003a3c, buffer_secondary: 0x20002686
[00:00:00.448,699] <inf> NRFX_EXAMPLE: 275
[00:00:00.448,699] <inf> NRFX_EXAMPLE: 275
[00:00:00.448,730] <inf> NRFX_EXAMPLE: 275
[00:00:00.448,730] <inf> NRFX_EXAMPLE: SAADC event: BUF_REQ
[00:00:00.449,066] <inf> NRFX_SAADC: m_cb address: 0x20003a3c, buffer_secondary: 0
[00:00:00.449,066] <inf> NRFX_EXAMPLE: 274
[00:00:00.449,096] <inf> NRFX_EXAMPLE: 275
[00:00:00.449,096] <inf> NRFX_EXAMPLE: 275
[00:00:00.449,096] <inf> NRFX_EXAMPLE: SAADC event: FINISHED

When I breakpoint in the 

nrfx_saadc_irq_handler()

and in the 

saadc_handler()

I get the same issue and the sampling goes right only one iteration. The output is like

[00:00:00.440,429] <inf> NRFX_EXAMPLE: Starting nrfx_saadc advanced non-blocking sampling with internal timer example.
[00:00:00.451,507] <inf> NRFX_SAADC: Function: nrfx_saadc_init, error code: NRFX_SUCCESS.
[00:00:00.451,568] <inf> NRFX_EXAMPLE: GPIOTE status: initialized
[00:00:00.451,599] <inf> NRFX_EXAMPLE: SAADC calibration will be started.
[00:00:00.451,599] <inf> NRFX_SAADC: nrfx_saadc_offset_calibrate called
[00:00:00.451,629] <inf> NRFX_EXAMPLE: Calibration started successfully
[00:00:14.430,664] <inf> NRFX_EXAMPLE: SAADC event: CALIBRATEDONE
[00:00:14.430,694] <inf> NRFX_EXAMPLE: saadc_mode_trigger() will be called to start the sampling.
[00:00:21.575,134] <inf> NRFX_EXAMPLE: SAADC event: READY
[00:00:26.013,061] <inf> NRFX_EXAMPLE: SAADC event: BUF_REQ
[00:00:30.260,742] <inf> NRFX_SAADC: m_cb address: 0x20003a3c, buffer_secondary: 0x20002686
[00:00:36.201,141] <inf> NRFX_EXAMPLE: 273
[00:00:36.201,141] <inf> NRFX_EXAMPLE: 273
[00:00:36.201,141] <inf> NRFX_EXAMPLE: 273
[00:00:43.427,459] <inf> NRFX_SAADC: m_cb address: 0x20003a3c, buffer_secondary: 0
[00:00:52.981,353] <inf> NRFX_EXAMPLE: 274
[00:00:52.981,353] <inf> NRFX_EXAMPLE: 275
[00:00:52.981,384] <inf> NRFX_EXAMPLE: 275
[00:00:56.099,060] <inf> NRFX_EXAMPLE: SAADC event: FINISHED

The NRFX_SAADC_EVT_BUF_REQ isnt called anymore.

The flowchart calls from

nrfx_saadc_irq_handler()

and 

saadc_handler()

when the issue occures is like

Can someone give me information why this behaviour is present and where to look or how to do some solution?

Nice regards,

Christoph