spi发送数据,两个字节之间的cs是长期低电平. 标准的spi不是两个字节之间cs会拉高一下再拉低吗? cs是可控的,比如发送10个字节,会拉低10个字节的长度.但每个字节之间没有拉高, clk也没有空隙. 感觉就是10个字节连发一样.
我的配置如下:
&spi0 {
clock-frequency = <100000000>;
pinctrl-0 = <&spi0_pins_a &spi0_pins_b>;
pinctrl-1 = <&spi0_pins_c>;
pinctrl-names = "default", "sleep";
/spi-supply = <®_dcdc1>;/
spi_slave_mode = <0>;
spi0_cs_number = <1>;
spi0_cs_bitmap = <1>;
sample_mode =<1>;
sample_delay = <10>;
spi0_cs_bitmap = <1>;
spi_dbi_enable = <0>;
status = "okay";
spi_board1@0 {
device_type = "spi_board1";
compatible = "spidev";
spi-max-frequency = <100000000>;
reg = <0x0>;
spi-rx-bus-width = <0x1>;
spi-tx-bus-width = <0x1>;
status = "okay";
};
示波器如下图
黄线是clk,蓝线是cs. cs一直拉低知道数据结束. 字节间没有拉高 用的是spi_test测试的.
求解 谢谢