ʾʹõԴ
SPI1_NSS    ------  PA15
SPI1_SCK    ------  PB3
SPI1_MISO   ------  PB4
SPI1_MOSI   ------  PB5


ʾḶ́
1ϵϵͳʱΪRCH72MHz
2ʼSPIGPIOţʹNVIC SPIжϣ
3SPI1ʼΪӻģʽͨģʽΪģʽ2λΪMSBģʽ
4SPI1ΪӻжϷʽͽݡ
