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STM32L4: Fix the UART RX & TX data reg bitmasks 

The existing logic was insufficient to properly handle odd and even
parity setting, e.g. serial_getc() returned 9-bit data for 8O1
transmission format.
pull/12341/head
Filip Jagodzinski 2020-01-28 14:09:01 +01:00 committed by Przemyslaw Stekiel
parent 7101e92d12
commit ae635d5cd4
1 changed files with 14 additions and 10 deletions
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24
targets/TARGET_STM/TARGET_STM32L4/serial_device.c
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@ -215,12 +215,15 @@ int serial_getc(serial_t *obj)
struct serial_s *obj_s = SERIAL_S(obj);
UART_HandleTypeDef *huart = &uart_handlers[obj_s->index];
/* Computation of UART mask to apply to RDR register */
UART_MASK_COMPUTATION(huart);
uint16_t uhMask = huart->Mask;
while (!serial_readable(obj));
if (obj_s->databits == UART_WORDLENGTH_8B) {
return (int)(huart->Instance->RDR & (uint8_t)0xFF);
} else {
return (int)(huart->Instance->RDR & (uint16_t)0x1FF);
}
/* When receiving with the parity enabled, the value read in the MSB bit
* is the received parity bit.
*/
return (int)(huart->Instance->RDR & uhMask);
}
void serial_putc(serial_t *obj, int c)
@ -229,11 +232,12 @@ void serial_putc(serial_t *obj, int c)
UART_HandleTypeDef *huart = &uart_handlers[obj_s->index];
while (!serial_writable(obj));
if (obj_s->databits == UART_WORDLENGTH_8B) {
huart->Instance->TDR = (uint8_t)(c & (uint8_t)0xFF);
} else {
huart->Instance->TDR = (uint16_t)(c & (uint16_t)0x1FF);
}
/* When transmitting with the parity enabled (PCE bit set to 1 in the
* USART_CR1 register), the value written in the MSB (bit 7 or bit 8
* depending on the data length) has no effect because it is replaced
* by the parity.
*/
huart->Instance->TDR = (uint16_t)(c & 0x1FFU);
}
void serial_clear(serial_t *obj)