PCF2127 and PCF2129 are high accuracy real-time-clock (RTC) module. This library provides simple interface to accessing clock information.
PCF2127 and PCF2129
PCF2127T is in SO16 package
The PCF2127 and the PCF2129 are a CMOS Real Time Clock (RTC) and calendar with an integrated Temperature Compensated Crystal (Xtal) Oscillator (TCXO) and a 32.768 kHz quartz crystal optimized for very high accuracy and very low power consumption.
Both of PCF2127 and PCF2129 have a selectable I2C-bus or SPI-bus, a backup battery switch-over circuit, a programmable watchdog function, a timestamp function, and many other features.
On addition to this, the PCF2127 has 512 bytes of general-purpose static RAM.
These 4 types of RTC modules are software compatible. So this library "PCF2127" can be used all of those.
This library only supports I2C to communicate with the PCF2127/PCF2129.
Main feature difference
|type||+/-3ppm accuracy range||512 bytes RAM||package|
|PCF2127T||-30℃ to +80℃||yes||SO16|
|PCF2127AT||-30℃ to +60℃||yes||SO20|
|PCF2129T||-30℃ to +80℃||not available||SO16|
|PCF2129AT||-15℃ to +60℃||not available||SO20|
Connection between MCU and PCF2127/PCF2129
These examples show how the RTC module can be connected via I2C bus.