PIC16F1823开发笔记(二)芯片研究以及第一个程序和汇编研究

1、综述：

总体来看，这款芯片功能齐全：

ADC

cps

EEPROM

DAC

DSM

USART

SR latch

timer(3)

2、存储

2048的RAM

3、寄存器详解

寄存器种类

3.1、核心寄存器

WREG|

PCLATH|

 INTCON|

INDF0

INTCON寄存器

状态寄存器

3.2、特殊功能寄存器

The Special Function Registers are registers used bythe application to control the desired operation of peripheral functions in the device. The registers associated with the operation of the peripherals are described in the appropriate peripheral chapter of this

data sheet.

这种类型的寄存器主要用于控制外设

3.3、通用寄存单元

The general purpose registers are a group of RAM locations in the file register that are used for data storage and scratch pad. Each location is 8 bits wide and can be used to store any data we want as long as it is 8 bit. Again, the number of RAM locations in the file register that are set aside for general purpose registers can vary from chip to chip, even among members of the same family. In the PIC micro-controllers, the space that is not allocated to the special function registers is used for general purpose registers. That means in a PIC chip with a thousand-byte file register, no more than 100 bytes are used for special function registers are the rest are used for general purpose registers. A larger GPR size means more difficulties in managing these registers if you use assembly language programming. In today’s high performance micro-controllers, with a over of thousand bytes of GPR, the job of managing them is handled by the C compilers. Indeed, the C compilers are the very reason we need a large GPR since it makes it easier for C compilers to store parameters and perform their jobs much faster.

4、点灯

#include

__CONFIG(0xFF32); //配置字

void main()

{

TRISA = 0; //设置a为输出模式

PORTA =0x00000001; //输出

while(1); //循环

}

5、汇编程序分析

下图 program memory 查看汇编代码

 Address           Disassembly          

   000    GOTO 0x1                      跳转到INDF

   001    CLRF 0x8                      清零BSR 

   002    GOTO 0x7f6                    跳转到0x7f6

   736    MOVWI [-1]FSR1               

   737    MOVWI [-1]FSR1                

   7F5    MOVWI [-1]FSR1               

   7F6    MOVLB 0                        BSR =0

   7F7    GOTO 0x7f8                    跳转到0x7f8

   7F8    MOVLB 0x1                      BSR = 1

   7F9    CLRF 0xc                      清零 PORTA

   7FA    MOVLW 0x1                      w= 1

   7FB    MOVLB 0                        BSR = 0 

   7FC    MOVWF 0xc                          w=0xc

   7FD    GOTO 0x7fe                    跳转到0x7fe

   7FE    GOTO 0x7fe                    跳转到0x7fe

   7FF    GOTO 0x1                      跳转到0x1

总结，这里我们要十分主义的是，我们每次改变BSR数值的时候，其实就是改变bank数据块，那么当BSR =1 的时候，我们再执行 movwf 0xc实际的起始地址是，bank1 的起始地址，所以这里的0xc实际上是指 0x8c TRISA