Posted on May 17, 2011 at 09:41 Has anyone checked whether the frequency of the spi clock matches with the equation fsclk = fpclk /(cpsdvr * ( 1 + scr)) ?
I seem to get only half of the equation when i see it in oscilloscope.
When fpclk = 48MHz, cpsdrv = 24 and scr = 0, i get 1MHz instead of 2MHz.
when i change scr to 1 i get only 0.5MHz.
my settings are:
fpclk = 48MHz
SSP_DeInit(SSP0);
SSP_StructInit(&SSP_InitStructure);
SSP_InitStructure.SSP_FrameFormat = SSP_FrameFormat_Motorola;
SSP_InitStructure.SSP_Mode = SSP_Mode_Master;
SSP_InitStructure.SSP_CPOL = SSP_CPOL_High;
SSP_InitStructure.SSP_CPHA = SSP_CPHA_1Edge;
SSP_InitStructure.SSP_DataSize = SSP_DataSize_8b;
SSP_InitStructure.SSP_ClockRate = 0;
SSP_InitStructure.SSP_ClockPrescaler = 24
SSP_Init(SSP0, &SSP_InitStructure);
SSP_Cmd(SSP0, ENABLE);
What is the correct equation for SSP clock?
thanks
vikram
