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Updated AVR32 demos and added AVR32 UC3B demo.

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This commit is contained in:
Richard Barry 2007-07-27 07:59:50 +00:00
parent 45e7e5ac55
commit 94c94d3c0e
164 changed files with 21458 additions and 3994 deletions
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29
Demo/AVR32_UC3/DRIVERS/USART/usart.c
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@ -11,7 +11,7 @@
* - AppNote:
*
* \author Atmel Corporation: http://www.atmel.com \n
* Support email: avr32@atmel.com
* Support and FAQ: http://support.atmel.no/
*
******************************************************************************/
@ -70,9 +70,12 @@ static __inline__ int usart_mode_is_multidrop(volatile avr32_usart_t *usart)
/*! \brief Calculates a clock divider (\e CD) that gets the USART as close to a
* wanted baudrate as possible.
*
* \todo manage the FP fractal part to avoid big errors
*
* Baudrate calculation:
* \f$ baudrate = \frac{Selected Clock}{16 \times CD} \f$ with 16x oversampling or
* \f$ baudrate = \frac{Selected Clock}{8 \times CD} \f$ with 8x oversampling.
* \f$ baudrate = \frac{Selected Clock}{8 \times CD} \f$ with 8x oversampling or
* \f$ baudrate = \frac{Selected Clock}{CD} \f$ with SYNC bit set to allow high speed.
*
* \param usart Base address of the USART instance.
* \param baudrate Wanted baudrate.
@ -90,20 +93,30 @@ static int usart_set_baudrate(volatile avr32_usart_t *usart, unsigned int baudra
// Baudrate calculation.
if (baudrate < pba_hz / 16)
{
// Use 16x oversampling.
usart->mr &=~ AVR32_USART_MR_OVER_MASK;
cd = pba_hz / (16 * baudrate);
// Use 16x oversampling, clear SYNC bit.
usart->mr &=~ (AVR32_USART_MR_OVER_MASK | AVR32_USART_MR_SYNC_MASK);
cd = (pba_hz + 8 * baudrate) / (16 * baudrate);
if ((cd >65535)) return USART_INVALID_INPUT;
}
else
else if (baudrate < pba_hz / 8)
{
// Use 8x oversampling.
usart->mr |= AVR32_USART_MR_OVER_MASK;
cd = pba_hz / (8 * baudrate);
// clear SYNC bit
usart->mr &=~ AVR32_USART_MR_SYNC_MASK;
cd = (pba_hz + 4 * baudrate) / (8 * baudrate);
if ((cd < 1)||(cd >65535)) return USART_INVALID_INPUT;
}
else
{
// set SYNC to 1
usart->mr |= AVR32_USART_MR_SYNC_MASK;
// use PBA/BaudRate
cd = (pba_hz / baudrate);
}
usart->brgr = cd << AVR32_USART_BRGR_CD_OFFSET;
return USART_SUCCESS;
@ -303,8 +316,6 @@ int usart_init_iso7816(volatile avr32_usart_t *usart, const iso7816_options_t *o
return USART_SUCCESS;
}
//! @}