初始化DA14531模块在电路中

Apologies if this question has been asked before. We recently purchased a number of DA14531 modules to integrate into a BLE-using project. At present we're still at the investigation phase.

To investigate how the module works, I hooked it up to a STM32L552 microcontroller (MCU) as recommended in section 7 of the datasheet:

* J14 TX on DA14531 to LPUART1 RX pin on the MCU.

* J10 RX在DA14531上的LPUART1 TX引脚MCU上。

* J12 RST on DA14531 to GPIO pin on the MCU, left floating for now.

I had naively assumed that the module would come pre-configured with Codeless AT commands from the manufacturer, but I am not getting any response to the simple "ATI" identification command off the module at either 57600bps or 115200bps.

Presumably I need to flash the module with the Codeless .hex file before it can be used. However, the module is already soldered in-circuit and connected to the MCU. And I don't currently have a development board to flash the module separately. Once we go to production we will want to flash and/or upgrade the module in-circuit rather than have to flash them separately before soldering in-place.

是否有一些方法使用上述引脚配置将模块放入引导加载程序模式？我发现SDK中的代码“DA145xx_sdk / 6.0.14.1114 / ultities / flash_programmer”似乎是在模块上运行的代码以执行引导加载。我可以轻松地编写自己的Flash实用程序以根据该信息在STM32L552内部运行。代码似乎指示引导加载程序使用1-Wire UART模式，我可能必须重新排列到MCU的接线。我在电路中有直线电阻，因此重新排列电线不应该是一个大型戏剧，我们将在下一个原型中修复PCB。

What is the sequence that I need to use to force the DA14531 module into its bootloader, whether the module is already flashed or not? Pull RST high and wait a bit? Toggle some other pin? It isn't clear to me from the documentation at the moment how to do this. A document describing the bootloading sequence would be very handy. I may have missed it while scanning, so sorry if I missed something obvious.

希望有一种方法可以使用源自源自工厂的DA14531模块来完成此操作。