STM32WB eddystone and sleep

Graduate

The cited example shows continuous packet transmission. What would be needed is a function to stop transmission and a deinit before activating sleep. Upon waking, the system will then proceed with a new init and new transmission. How should the stop function be implemented? Thanks.

STM32WB55 BLE and LPM - STMicroelectronics Community

ST Employee

Hello,

please check this topic as it may be helpful for you.

For using low power mode, you just have to enable it in app_conf.h file #define CFG_LPM_SUPPORTED 1.

The sequencer will automatically enter low power mode if there are no pending tasks.

Regarding the stop function, you could use a timer server which would periodically start advertising.

Best regards,

ST support

Graduate

I @FilipKremen and thanks for your answer.

I read the suggested post (and also replied to it) and set CFG_LPM_SUPPORTED to 1.
However, it still doesn't work.
If I set "BT SIG Beacon" = disabled in the STM32CubeMX (because I only want to transmit data using the advertiser's manufacture-specific data), I have no problem putting the microcontroller to sleep and stopping the transmission of BLE packets, then waking it up and starting the cycle again.
On the other hand, when I set "BT SIG Beacon" = EDDYSTONE_TLM_BEACON, I have problems.
When the microcontroller goes to sleep, the sniffer continuously detects packet transmission. Furthermore, I can't wake the microcontroller from sleep.

Best regards

ST Employee

Hello,

can you please send me your project?

Thank you.

Best regards,

Filip Kremen

Graduate

Hello.

Sorry, but I cannot disclose the project due to confidentiality.

ST Employee

Do you use sequencer with low power manager, or do you have your own solution?

What is your current consumption requirement? Do you have any power consumption waveform to share?

Best regards,

Filip Kremen

Graduate

What exactly do you mean by "sequencer with low power manager"?
The current requirement is, of course, as low as possible. I don't have waveforms; our customer performed all these measurements directly.

Graduate

If you mean the "sequencer" entry in stm32cubeMX, this is enabled.

Utility:Sequencer - stm32mcu

ST Employee

Please read this Wiki page below for more information about sequencer.

For the low power manager please visit section 4.6 in AN.

How to build wireless applications with STM32WB MCUs - Application note

I'm attaching the Beacon example with stop mode enabled.

Please let me know if it works on your side, you can see the current consumption of this application below.

Also, before measurement please remove JP2 and everything from JP5.

Best regards,

Filip Kremen

Graduate

Thak you @FilipKremen.

I understand what the example code you provided does. But that's not what I want to do.
I want the microcontroller to go to sleep for a certain amount of time (a few dozen minutes) after performing certain operations (acquisition of quantities, updating the EddystoneTLM_InitStruct structure for transmission with the Eddystone TLM protocol). To put the microcontroller to sleep, I use the following sequence:

HAL_LPTIM_Counter_Start_IT(&hlptim1, hlptim_prescaler);

HAL_SuspendTick();
HAL_NVIC_DisableIRQ(RTC_WKUP_IRQn);
HAL_NVIC_DisableIRQ(IPCC_C1_RX_IRQn);
HAL_NVIC_DisableIRQ(IPCC_C1_TX_IRQn);
HAL_NVIC_DisableIRQ(HSEM_IRQn);
HAL_PWREx_EnterSTOP2Mode(PWR_SLEEPENTRY_WFI);

Upon waking up:

HAL_LPTIM_Counter_Stop_IT(&hlptim1);
HAL_NVIC_EnableIRQ(IPCC_C1_RX_IRQn);
HAL_NVIC_EnableIRQ(IPCC_C1_TX_IRQn);
HAL_NVIC_EnableIRQ(HSEM_IRQn);
HAL_InitTick(TICK_INT_PRIORITY);
HAL_ResumeTick();

Everything works correctly: data transmission, the microcontroller in sleep, and waking up.
The problem is that even when the microcontroller is in sleep, I can still detect some transmission activity from my device using the sniffer (I haven't been able to identify what type of transmission it is).

This is a big problem because I'm consuming power (due to this activity) even when the microcontroller is asleep. Apparently, part of the firmware (stack) residing on CPU2 continues to send BLE packets. How can I stop this activity?