static rt_err_t lpc_configure(struct rt_serial_device *serial, struct serial_configure *cfg)
{
struct lpc_uart *uart;
UART_BAUD_T baud;
UART_CFG_T UART_cfg;
RT_ASSERT(serial != RT_NULL);
uart = (struct lpc_uart *)serial->parent.user_data;
/* Initialize UART Configuration parameter structure to default state:
* Baudrate = 115200 b
* 8 data bit
* 1 Stop bit
* None parity
*/
/* Set up baudrate parameters */
baud.clk = Chip_Clock_GetAsyncSyscon_ClockRate(); /* Clock frequency */
baud.baud = cfg->baud_rate; /* Required baud rate */
baud.ovr = 0; /* Set the oversampling to the recommended rate */
baud.mul = baud.div = 0;
if(!baud.mul)
{
_UART_CalcMul(&baud);
}
_UART_CalcDiv(&baud);
/* Set fractional control register */
LPC_ASYNC_SYSCON->FRGCTRL = ((uint32_t) baud.mul << 8) | 0xFF;
/* Configure the UART */
UART_cfg.cfg = UART_CFG_8BIT;
UART_cfg.div = baud.div; /* Use the calculated div value */
UART_cfg.ovr = baud.ovr; /* Use oversampling rate from baud */
UART_cfg.res = UART_BIT_DLY(cfg->baud_rate);
/* P254,255,246 */
uart->UART->OSR = (UART_cfg.ovr - 1) & 0x0F;
uart->UART->BRG = (UART_cfg.div - 1) & 0xFFFF;
uart->UART->CFG = UART_CFG_ENABLE | (UART_cfg.cfg & ~UART_CFG_RES);
return RT_EOK;
}
/* Configure UART ROM Driver and pripheral */
static int uartrom_config(void)
{
UART_CFG_T cfg;
UART_BAUD_T baud;
/* Set up baudrate parameters */
baud.clk = Chip_Clock_GetAsyncSyscon_ClockRate(); /* Clock frequency */
baud.baud = UART_BAUD_RATE; /* Required baud rate */
baud.ovr = 0; /* Set the oversampling to the recommended rate */
baud.mul = baud.div = 0;
if (ROM_UART_CalBaud(&baud) != LPC_OK) {
/* Unable to calculate the baud rate parameters */
while (1) {}
}
/* Set fractional control register */
Chip_SYSCON_SetUSARTFRGCtrl(baud.mul, 255);
/* See if the calculated baud is < +/- UART_BUAD_ERR% of the required baud */
if (ABS(baud.baud - UART_BAUD_RATE) > (UART_BAUD_RATE * UART_BUAD_ERR) / 100) {
/* WARNING: Baud rate is has more than UART_BUAD_ERR percentage */
/* Try to auto-detect the Oversampling rate by setting baud.ovr to 0 */
while (1) {}
}
/* Configure the UART */
cfg.cfg = UART_CFG_8BIT | UART_CFG_BRKRX;
cfg.div = baud.div; /* Use the calculated div value */
cfg.ovr = baud.ovr; /* Use oversampling rate from baud */
cfg.res = UART_BIT_DLY(UART_BAUD_RATE);
/* Configure the UART */
ROM_UART_Configure(hUART, &cfg);
NVIC_ClearPendingIRQ(UART0_IRQn);
NVIC_EnableIRQ(UART0_IRQn);
return 0;
}
