fsfw-hal/stm32h7/spi/spiDefinitions.cpp

53 lines
1.4 KiB
C++

#include "spiDefinitions.h"
void spi::assignSpiMode(SpiModes spiMode, SPI_HandleTypeDef& spiHandle) {
switch(spiMode) {
case(SpiModes::MODE_0): {
spiHandle.Init.CLKPolarity = SPI_POLARITY_LOW;
spiHandle.Init.CLKPhase = SPI_PHASE_1EDGE;
break;
}
case(SpiModes::MODE_1): {
spiHandle.Init.CLKPolarity = SPI_POLARITY_LOW;
spiHandle.Init.CLKPhase = SPI_PHASE_2EDGE;
break;
}
case(SpiModes::MODE_2): {
spiHandle.Init.CLKPolarity = SPI_POLARITY_HIGH;
spiHandle.Init.CLKPhase = SPI_PHASE_1EDGE;
break;
}
case(SpiModes::MODE_3): {
spiHandle.Init.CLKPolarity = SPI_POLARITY_HIGH;
spiHandle.Init.CLKPhase = SPI_PHASE_2EDGE;
break;
}
}
}
uint32_t spi::getPrescaler(uint32_t clock_src_freq, uint32_t baudrate_mbps) {
uint32_t divisor = 0;
uint32_t spi_clk = clock_src_freq;
uint32_t presc = 0;
static const uint32_t baudrate[] = {
SPI_BAUDRATEPRESCALER_2,
SPI_BAUDRATEPRESCALER_4,
SPI_BAUDRATEPRESCALER_8,
SPI_BAUDRATEPRESCALER_16,
SPI_BAUDRATEPRESCALER_32,
SPI_BAUDRATEPRESCALER_64,
SPI_BAUDRATEPRESCALER_128,
SPI_BAUDRATEPRESCALER_256,
};
while( spi_clk > baudrate_mbps) {
presc = baudrate[divisor];
if (++divisor > 7)
break;
spi_clk = ( spi_clk >> 1);
}
return presc;
}