This repository contains the embedded firmware of the DebugDongle, a USB power supply and serial port for prototype debugging.
- Bidirectional UART connection is relayed to the USB serial port.
- Power is supplied to an external board: Either the USB voltage or the output of the 3.3V step-down converter. The selection can be made by an onboard switch or by the USB HID interface. The voltage level is indicated by a dedicated LED.
- The onboard Li-ion battery charger IC can charge a connected battery. The charging is managed by the software and can be supervised by the USB HID interface. Indicator LEDs give visual feedback on the USB power's presence and the ongoing charging.
- An independent USB HID sensor interface provides core voltage and temperature, and ambient illuminance measurements.
- The bootloader's DFU interface is mapped on the USB device. The DFU updater client can use the same interface in application mode to send the device to update mode.
The firmware is written for an STM32F042F6 device (TSSOP-20 package, 32kB flash, 6kB SRAM, 48MHz clock). By changing the BSP layer it is possible to port the application to any STM32 device which is supported by STM32_XPD.
This firmware uses DFU bootloader, which is built for this target with the following parameters:
TARGET_HEADER="\<stm32f040x6.h\>" SERIES=STM32F0 FLASH_APP_ADDRESS=0x08002000, FLASH_APP_SIZE=24*1024, FLASH_TOTAL_ERASE_TIME_ms=480, USBD_VID=0xFFFF, USBD_PID=0xF042, VDD_VALUE_mV=3300
For a standalone operation the DFU interface must not be mounted on the application USB device, and the application flash offset has to be removed.
Built with GCC ARM tools.