1） stm32都可以通过默认的串口1烧写（必须是默认的串口），这是因为stm32内置的固件只支持默认串口1.
2）串口需要max232等串口电路下载；
3）如不能下载，请检查uart电路是不是连接在默认串口1上，检查串口电路是否正常通讯

不能支持！
Bootloader unavailability on STM32F105xx/STM32F107xx devices
with a date code below 937
Description
The bootloader cannot be used if the USART1_RX (PA10), USART2_RX (PD6, remapped),
CAN2_Rx (PB5, remapped), OTG_FS_DM (PA11), and/or OTG_FS_DP (PA12) pin(s) are
held low or left floating during the bootloader activation phase.
The bootloader cannot be connected through CAN2 (remapped), DFU (OTG FS in Device
mode), USART1 or USART2 (remapped).
On 64-pin packages, the USART2_RX signal remapped PD6 pin is not available and it is
internally grounded. In this case, the bootloader cannot be used at all.
Workaround
• For 64-pin packages
None. The bootloader cannot be used.
• For 100-pin packages
Depending on the used peripheral, the pins for the unused peripherals have to be kept
at a high level during the bootloader activation phase as described below:
– If USART1 is used to connect to the bootloader, PD6 and PB5 have to be kept at a
high level.
– If USART2 is used to connect to the bootloader, PA10, PB5, PA11 and PA12 have
to be kept at a high level.
– If CAN2 is used to connect to the bootloader, PA10, PD6, PA11 and PA12 have to
be kept at a high level.
– If DFU is used to connect to the bootloader, PA10, PB5 and PD6 have to be kept
at a high level.

参考文件《AN2606  Application note  STM32 microcontroller system memory boot mode》

肯定可以

可以的。与103是一样的