OTA Update - What is the boot sequence?

[Exeu]

Hi, 

i am currently trying to wrap my head around the OTA Application Update Procedure which STM32 recommends to do.

So what i understand is:

There is the BLE_Ota example (which basically should take another application binary and write it to some memory)

This BLE_Ota app is located at 0x08000000 -> So the device should first enter the BLE_Ota app.

The "real" application is then located at 0x08007000.

I hope this is correct so far.

Now i would have the question: Who is deciding now that we need a "jump" to address 0x08007000?

I can not really find this in the BLE_Ota app somehow, but from my understanding the BLE_Ota app at some point in time should decide if it should go to 0x08007000 and let the real application run?

Maybe this is also handled by some internals (or even the coprocessor?).

I know that after a "upload" in the OTA_App is triggering a reset. But interesting for me would be: What is the flow after exactly this reset? Now the controller should end up in 0x08007000 somehow.

Any advise / help is appreciated.

Thank you

[STTwo-32]

Hello @Exeu 

I think you should have a look at this Video together with the AN5247 to understand how OTA for an STM32WB works exactly. 

Best Regards.

STTwo-32

[Exeu]

Thank you very much. Actually the Video helped me here as it was showing "who" is causing the jump actually.

Another Question:

The OTA Reboot BLE Characteristic is sth. the controller is registering automatically?

I see that the feature is registered here:

 /**
 * Initialization of ADV - Ad Manufacturer Element - Support OTA Bit Mask
 */
#if (BLE_CFG_OTA_REBOOT_CHAR != 0)
 a_ManufData[sizeof(a_ManufData)-8] = CFG_FEATURE_OTA_REBOOT;
#endif /* BLE_CFG_OTA_REBOOT_CHAR != 0 */

And then later:

ret = aci_gap_update_adv_data(sizeof(a_ManufData), (uint8_t*) a_ManufData);

So we are just setting the flag in the advertising data.

Who is now seeing that this flag is set and is registering the Characteristics (so that i can from outside write to it).

And specially who handles that there is a reboot request written to this char?

 

[STTwo-32]

Hello @Exeu 

This is a new question. So, you need to create a new post for it after selecting the comment that answer your original question as best answer.

Best Regards.

STTwo-32