Figure 3 display the highlighted 9 pin connector J202 on bottom side of SoM_IoT_1V2 printed circuit board. This connector allocate the large-scale integrated circuit R-IN32M3-EC with external SPI and additional SYNC signals. Furthermore the power supply pins VCC33 and GROUND are connected on J202.
Pin 1 (VCC33) and pin 2 (GND) should be connect with external DC voltage source. The SoM_iRJ45 IoT is specified for an input voltage range of 3,15V DC to 3,45V DC.
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Pin 3 has chip select (CS) function for R-IN32M3-EC Clocked Serial Interface H (CSIH) which works in Slave Mode at CSIH channel 0. The used chip select sink for this R-IN32M3-EC based module is Port P70, Port P71 drives permanently to GND level.
Pin 4 connect the RESETZ ball of R-IN32M3-EC. So an external reset signal can initialize the CPU core and the internal peripheral modules.
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