Posted on May 17, 2011 at 14:06Domen:
I have tried all 4 CPOL/CPHA combinations without luck.
As for the SPI initialization code. Check the attached file if you would prefer to see it in context. Below is a brief explanation of what I believe are the relevant components.
I started by setting up the clocks:
RCC_PCLK2Config(RCC_HCLK_Div2);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_SPI1, ENABLE);
Then I setup the GPIO pins:
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 | GPIO_Pin_5 | GPIO_Pin_6;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_Init(GPIOA, &GPIO_InitStructure);
Then I configure the peripheral:
SPI_InitStructure.SPI_Direction = SPI_Direction_1Line_Rx;
SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;
SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;
SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;
SPI_InitStructure.SPI_NSS = SPI_NSS_Hard;
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_16;
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_InitStructure.SPI_CRCPolynomial = 7;
SPI_Init(SPI1, &SPI_InitStructure);
Then I enable hardware slave select (NSS):
SPI_SSOutputCmd(SPI1, ENABLE);
Finally, in a loop I enable the peripheral for just long enough to incite the ADC to send data and then I disable it. It's at this point that I expect data to appear in SPI1-DR but no luck.
Dustin
