如果实在找不到原因了, 再告诉你一招: 摘自 AN2606
● The peripheral RX pins not used in this bootloader have to be kept at a known (low or high) level, and should not be left floating during the detection phase as described below:
– If USART1 is used to connect to the bootloader, the USART2_RX (PA15) pin has to be kept at a high or low level and must not be left floating during the detection phase.
– If USART2 is used to connect to the bootloader, the USART1_RX (PA10) pin has to be kept at a high or low level and must not be left floating during the detection phase.
● The peripheral to be used has to be connected through an RS232 serial interface (example, ST3232 RS232 transceiver) which must be:
– directly connected to the USART1_RX (PA10) and USART1_TX (PA9) pins when USART1 is used
– directly connected to the USART2_RX (PA15) and USART2_TX (PA14) pins when USART2 is used.
|
楼主
