AN3123

OS-independent SPEAr UART HAL

Doc ID 16862 Rev 2

25/30

Apart from the above table, if any other option is given then it is an invalid word length

option.

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StopBitSelect: If it is already zero then OneStopBit. If it is equal to STOP2 then two stop

bits otherwise invalid stop bit select.

●

FIFOStatus: Its valid inputs are FIFO_Enable or FIFO_Disable (already zero),

otherwise it is a case of invalid FIFO status.

●

TxWatermarkLevel: The interrupt FIFO level is already set to 1/8

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RxWatermarkLevel: The Interrupt FIFO Level is already set to 1/8

10.5

UART_Transmit()

This API allows to start transmit a given number of characters. It writes character by

character.

t_UARTError UART_Transmit(struct spear_uart_config *dev, u32

NumOfCharToTx, char *Buffer)

●

NumOfCharToTx: This is the number of characters to be transmitted

●

Buffer: This is the pointer to the characters to be transmitted

10.6

UART_Receive()

This routine is used to start receiving a given number of characters. It reads character by

character.

Table 16.

TxWatermarkLevel values

Option

Value

OneByEight

-

OneByFour

TX_FIFO_TRIG_1BY4

OneByTwo

TX_FIFO_TRIG_1BY2

ThreeByFour

TX_FIFO_TRIG_3BY4

SevenByEight

TX_FIFO_TRIG_7BY8

Table 17.

RxWatermarkLevel values

Option

Value

OneByEight

-

OneByFour

RX_FIFO_TRIG_1BY4

OneByTwo

RX_FIFO_TRIG_1BY2

ThreeByFour

RX_FIFO_TRIG_3BY4

SevenByEight

RX_FIFO_TRIG_7BY8