基于I2C总线的日历时钟PCF8563在MSP430中的应用

以开发的智能型电网电量综合监控仪上用到的日历时钟芯片PCF8563为例,通过分析TI公司的超低功耗MSP430系列单片机的特点和端口使用情况、与传统的51系列单片机的区别、用于该低功耗单片机系统的电源管理芯片RH5RL36AA的使用以及I2C总线的特点和使用条件,提出了一种基于MSP430F149单片机的简单高效的I2C总线接口技术,同时给出了该接口技术的C430程序.在给出程序的同时,亦分析了在该单片机的调试环境AQ430 Tools下,编译系统执行C程序时所用到的汇编语句,通过计算I2C总线置0和1过程中用到的汇编指令周期,提出了一种简化程序代码和提高执行速度的程序设计方法.实际调试证明,在MSP430系列单片机上应用I2C总线技术和简化的程序设计,不但结构简单、使用方便,而且性能很可靠.

Application of PCF8563 on MSP430 Series MCU

By analyzing the characteristics and I/O ports of MSP430 MCU, the difference between MSP430 MCU and traditional MCS51 series MCU, and the usage of power management chip RH5RL36AA and the characteristics of I2C (Inner IC Bus), this paper takes the calendar clock chip PCF8563, which is used in an intelligent device for monitoring the electricity over an electric network,as an example to propose a simple and highly-effective I2C bus interface technique for MSP430F149 MCU. It also provides the C430 working program for the interface. According to the calculation of the execution cycles of some assembly language instructions for the I2C bus operation, the paper also puts forward a program design method for a simplified coding scheme and a faster execution speed. The testing results show that by using the proposed I2C bus technique and program design method the MSP430 series MCU has not only a simple structure (easy to configure), but also a very reliable performance.