RTC EoF-001
Description
This RTC module use DS3231 as its Real-Time Clock chip which has build-in crystal oscillator. This RTC module communicates with Raspberry Pi through I2C bus.DS3231 is a low power consumer RTC chip and whose back up supply is a 0.2uF Super-Capacitor,which can keep work for a week at least after power down
Compatibility List
- Compatibility
| Platform | Super Capacitor RTC | Notes |
|---|---|---|
| Raspberry Pi 4 Model B | √ | |
| Raspberry Pi 3 Model B Plus | √ | |
| Raspberry Pi zero | √ | |
| Raspberry Pi zero W | √ | |
| Raspberry Pi 3 Model B | √ | |
| Raspberry Pi 2 Model B | √ | |
| Raspberry Pi Model B+ | √ | |
Technical Details
| Type | value |
|---|---|
| Work Voltage | 5V |
| Weight | 4.35g |
| Maximum Current | 1.5mA |
| VBAT Current | 800nA |
| work temprature | 0～+50℃ |
| Crystal Oscilator | Epson 20 ppm |
| scale | 22x26x18.6(mm) |
| Battery | CR1220 |
| RTC chip | DS3231 |
| mount hole | 2*5 Stacking Header |
Overview
Schematic
LCD module scale
DT Overlays Used
With DT enabled, this becomes a line in config.txt:
dtoverlay=i2c-rtc ds3231
It can adds support for a number of I2C Real Time Clock devices
Learn
- Type in [sudo raspi-config] set up raspberry pi and prepare to enable i2c interface
- select Advanced Options
- select I2c
- select yes enable I2C
- type in [sudo vim.tiny /etc/modules] to open file modules
- add i2c-dev device like picture below
- install i2c-tools ,type in [sudo apt-get install i2c-tools]
- type in [sudo reboot] wait the raspberry pi restart ,Then type in [sudo i2cdetect –y 1], if RTC works ,it should be like picture below
- Type in [sudo su –] change root user,then Type in [modprobe i2c-dev] to load I2C device
- Type in [echo "ds1307 0x68" > /sys/class/i2c-adapter/i2c-1/new_device] add RTC to system
- Then you can use “hwclock” command to use this RTC module
If you want to know more about hwclock command you can type in “man hwclock” to get details A brief description like following: Command [hwclock –r] to get RTC time Command [hwclock -w]set the system time to RTC time Like following
