Difference between revisions of "RTC EoF-001"

From 52Pi Wiki
Jump to navigation Jump to search
(Compatibility List)
(Learn)
Line 73: Line 73:
 
<br>[[Image:RTC CCAP02.png|700px]]
 
<br>[[Image:RTC CCAP02.png|700px]]
  
 +
==DT Overlays Used==
 +
With DT enabled, this becomes a line in config.txt:
 +
 +
    dtoverlay=i2c-rtc ds3231
 
==Learn==
 
==Learn==
 
*Type in [sudo raspi-config] set up raspberry pi and prepare to enable i2c interface
 
*Type in [sudo raspi-config] set up raspberry pi and prepare to enable i2c interface
Line 101: Line 105:
 
Like following
 
Like following
 
<br>[[Image:RTC_tech12.png|700px]]
 
<br>[[Image:RTC_tech12.png|700px]]
 +
 
==Attachment==
 
==Attachment==
 
<div id="tech1"></div>
 
<div id="tech1"></div>
 
<br>[[media:DS3231.pdf|ds3231 date sheet]]
 
<br>[[media:DS3231.pdf|ds3231 date sheet]]

Revision as of 11:36, 22 April 2020

Raspberry Pi RTC Module With Battery

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


CAP RTC.jpg

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

RTC CCAP01.png

LCD module scale


RTC CCAP02.png

DT Overlays Used

With DT enabled, this becomes a line in config.txt:

   dtoverlay=i2c-rtc ds3231

Learn

  • Type in [sudo raspi-config] set up raspberry pi and prepare to enable i2c interface


RTC tech02.png

  • select Advanced Options


RTC tech03.png

  • select I2c


RTC tech04.png

  • select yes enable I2C


RTC tech05.png

  • type in [sudo vim.tiny /etc/modules] to open file modules


RTC tech06.png

  • add i2c-dev device like picture below


RTC tech07.png

  • install i2c-tools ,type in [sudo apt-get install i2c-tools]


RTC tech08.png

  • 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


RTC tech09.png

  • Type in [sudo su –] change root user,then Type in [modprobe i2c-dev] to load I2C device


RTC tech10.png

  • Type in [echo "ds1307 0x68" > /sys/class/i2c-adapter/i2c-1/new_device] add RTC to system


RTC tech11.png

  • 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
RTC tech12.png

Attachment


ds3231 date sheet