Serial communication parity bit.

[Sarah1]

The data frame of BootLoader of STM32F207 : a start bit, data bits, even parity bit and a stop bit.The USART data contains a even parity to send to the BootLoader, then it replies with the correct data.

Theoretically, USART data has no parity bit, then the BootLoader will judge it as an error after receiving it.But in practice, BootLoader can reply with the correct information.Why the BootLoader can resolve data without parity bits?

[Tesla DeLorean]

Wrong sub-forum..

The STM32 doesn't "receive" the 0x7F byte but rather uses it as a timing pattern to auto-baud. No sure why it is worth worrying about this when it is documented to expect 8E1, and works properly when used?

[Sarah1]

The STM32 receives "0x7F",it enters the system memory boot mode.And then,if BootLoader receives "0x00 0xFF" without parity bit,why it can works properly?

How can we send data when the sender does not support parity bit and BootLoader requires even parity?