/**
* \brief Set the baudrate using precalculated BAUDCTRL values from PROGMEM
*
* \note This function only works for cpu_hz 2Mhz or 32Mhz and baudrate values
* 1200, 2400, 4800, 9600, 19200, 38400 and 57600.
*
* \param usart The USART module.
* \param baud The baudrate.
* \param cpu_hz The CPU frequency.
*
*/
void usart_set_baudrate_precalculated(USART_t *usart, uint32_t baud,
uint32_t cpu_hz)
{
uint8_t baud_offset;
uint16_t baudctrl = 0;
baud_offset = usart_get_baud_offset(baud);
if (cpu_hz == 2000000UL) {
baudctrl = PROGMEM_READ_WORD(baudctrl_2mhz + baud_offset);
} else if (cpu_hz == 32000000UL) {
baudctrl = PROGMEM_READ_WORD(baudctrl_32mhz + baud_offset);
} else {
/* Error, system clock speed or USART baud rate is not supported
by the look-up table */
Assert(false);
}
if (baud_offset != USART_BAUD_UNDEFINED) {
(usart)->BAUDCTRLB = (uint8_t)((uint16_t)baudctrl);
(usart)->BAUDCTRLA = (uint8_t)((uint16_t)baudctrl >> 8);
}
/**
* \brief Set the baudrate using pre calculated BAUDCTRL values stored in program
* memory
*
* \note This function only works for cpu_hz 1Mhz, 8Mhz or 16Mhz and baudrate values
* 1200, 2400, 4800, 9600, 19200, 38400 and 57600.
*
* \param usart The USART module.
* \param baud The baudrate.
* \param cpu_hz The CPU frequency.
*
*/
void usart_set_baudrate_precalculated(USART_t *usart, uint32_t baud,
uint32_t cpu_hz)
{
uint8_t baud_offset;
uint16_t baudctrl = 0;
baud_offset = usart_get_baud_offset(baud);
if (cpu_hz == 1000000UL) {
baudctrl = PROGMEM_READ_WORD(baudctrl_1mhz + baud_offset);
} else if (cpu_hz == 8000000UL) {
baudctrl = PROGMEM_READ_WORD(baudctrl_8mhz + baud_offset);
} else if (cpu_hz == 16000000UL) {
baudctrl = PROGMEM_READ_WORD(baudctrl_16mhz + baud_offset);
} else {
/* Error, system clock speed or USART baud rate is not supported
* by the look-up table */
Assert(false);
}
if (baud_offset != USART_BAUD_UNDEFINED) {
usart->UBRR = baudctrl;
}
}