
RAK411 PROGRAMMING MANUAL
V1.7
COPYRIGHT ©
SHENZHEN RAKWIRELESS TECHNOLOGY CO., LTD
ETDX1603021415
4
3 SPI Interface
RAK411 communicates with the host through a standard 4-wire SPI interface. SPI clock
supports maximum 16MHZ and optional SPI-INT pin. The SPI interface configuration diagram is
as follows:
3.1 Hardware Connection
3.2 SPI Timing Diagram
SPI_CS
SPI_CL
SPI_MO
SPI_MIS
CPOL = 0--------------------------------------SCK is idle in low level voltage
CPHA = 0--------------------------------------Data is latched on clock rising edge, while
transmitted on clock falling edge
MSB_FIRST--------------------------------------MSB is first sent8 BIT
MODE----------------------------------------------Data length is 8
bitsCS-----------------------------------------------Slave selective signal is effective low