diff options
Diffstat (limited to 'chip/stm32/uart.c')
| -rw-r--r-- | chip/stm32/uart.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/chip/stm32/uart.c b/chip/stm32/uart.c index bafca58c46..6be0790c63 100644 --- a/chip/stm32/uart.c +++ b/chip/stm32/uart.c @@ -176,7 +176,14 @@ static void uart_interrupt(void) #if defined(CHIP_FAMILY_STM32F4) STM32_USART_SR(UARTN_BASE) &= ~STM32_USART_SR_TC; #else - STM32_USART_ICR(UARTN_BASE) |= STM32_USART_SR_TC; + /* + * ST reference code does blind write to this register, as is + * usual with the "write 1 to clear" convention, despite the + * datasheet listing the bits as "keep at reset value", (which + * we assume is due to copying from the description of + * reserved bits in read/write registers.) + */ + STM32_USART_ICR(UARTN_BASE) = STM32_USART_SR_TC; #endif if (!(STM32_USART_SR(UARTN_BASE) & ~STM32_USART_SR_TC)) return; |