Radio Platform Notes

EMW3165 Radio Platform Notes

Rewair uses WICED 3.3.1 with a custom AWAIR platform overlay. The tracked application and platform sources are synchronized into the sibling WICED SDK checkout by the repository build scripts; see Building and Flashing.

Platform differences

The WICED reference platform is a BCM943362WCD4 with an STM32F205. The Awair radio module is an EMW3165 with an STM32F411, so Rewair overrides the MCU layout, UART assignments, SPI pins, flash handling, and idle behavior. The complete board interconnect is documented in Hardware Architecture.

Firmware constraints

• F411 internal flash is 512 KiB. The Rewair application occupies sectors 3–7; the OTA bootloader uses an F411-specific erase path because the generic WICED F4 helper continues into nonexistent sectors on this part.
• DCT occupies the internal sectors between the bootloader and application. Normal build, release-install, and flash scripts preserve it unless a reset is explicitly requested.
• WICED_DISABLE_MCU_POWERSAVE keeps SysTick active in the ordinary WFI idle path. The SDK's tickless path was observed missing a short wake-up and later tripping the watchdog.
• USART1 stdio is disabled because the BI201 owns that peripheral. Runtime diagnostics use SWD-readable state instead of the old serial console.
• The F103 link uses USART2 with RTS/CTS. F411 RTS is asserted before the sensor MCU leaves reset so its boot-time output is not blocked.

Low-level diagnostics

tools/legacy/emw3165_sensor_console is a small bare-metal application that talks to the F103 without starting WICED or Wi-Fi. Use it to distinguish a sensor-protocol problem from the WICED UART/DMA path. Current investigation state belongs in Project Status, not on this platform page.