User's Manual

Table Of Contents
SIM7090G User Manual V1.01
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The following figure shows the SPI bus reference design.
Figure 19: SPI master mode circuit
Figure 20: SPI slave mode circuit
The SPI_MOSI (49 pin) function is FAST BOOT function before system boot-up, so the level on this pin
cannot be high before the system boot-up, otherwise the module will not start normally.
NOTE