你好,我用的是AD7490
SCLK引脚说明:
Serial Clock. Logic input. SCLK provides the serial clock for accessing data from the part. This
clock input is also used as the clock source for the conversion process of the AD7490.
然后这个SCLK需要20MHZ,这个SCLK应该也属于SPI的时钟脚,直接接STM32的SPI对应的SCLK但是不知道如何让单片机提供20MHZ的频率(),STM32的SPI的频率只有几个可选的频率:
Select the BR[2:0] bits to define the serial clock baud rate (see SPI_CR1 register).
Bits 5:3 BR[2:0]: Baud rate control
000: fPCLK/2
001: fPCLK/4
010: fPCLK/8
011: fPCLK/16
100: fPCLK/32
101: fPCLK/64
110: fPCLK/128
111: fPCLK/256。