Datasheet of CM4 Industrial V1.4

EDA Technology Co.,LTD

– Electronics Development Accelerator

4 Internal Interface

4.1 SPI Flash

CM4 Industrial is for customers to store data.

SPI Flash is mounted on the spi-1 bus of CM4.

Spi-1 bus pin definition:

#

Signal

CM4 Pinout

1

SPI_CS

GPIO16

2

SPI_SCK

GPIO21

3

SPI_MISO

GPIO19

4

SPI_MOSI

GPIO20

4.2 RTC

CM4 Industrial is integrated with RTC. For the version sold in China, we will install CR1220 button cell

(RTC backup power supply) by default when shipping. In this way, the system can be guaranteed to

have an uninterrupted and reliable clock, which is not affected by factors such as equipment power

down. RTC clock chip is mounted on i2c-1 bus, and the device address is 0x51.

I2c-1 bus pin definition:

#

Signal

CM4 Pinout

1

SDA1

GPIO2

2

SCL1

GPIO3

WARN: Because logistics transportation does not support packaging with batteries, the factory

equipment is not pre-installed with CR1220 batteries. Before using RTC, you should prepare a

CR1220 button cell to install it.

4.3 Buzzer

CM4 Industrial is equipped with a buzzer, which can be turned on and off through GPIO.