SPI-MCP41XXX.rar_4100xxx_41xxx_MCP4100_MCP4100规格书_mcp41XX 程序

# include <reg52.h> #include <intrins.h> #define uchar unsigned char #define uint unsigned int sbit SCK = P1^0; sbit si = P1^1; sbit CS = P1^2; sbit key_add = P1^3; sbit key_cut = P1^4; #define DATA_D0 0x11//即对C1C0：01,P1P0：01选择 #define CLEAR_D0 0x41 uchar counter =0; void delay(uchar x) { while(x--); } //写指令，写数据 void write_mcp4110(uchar cmd,uchar dat) { uchar i; uint num; num = cmd*256+dat; CS = 1; SCK = 0; CS = 0; for(i = 0 ;i <16; i++) { /*if(num&0x8000) si = 1; else si = 0; */ si = (bit)(num&0x8000); SCK = 0; num = num<<1; SCK = 1; } CS = 1; } void write_8bit(uchar cmd) { uchar i; CS = 1; SCK = 0; CS = 0; for(i = 0 ;i <8; i++) { if(cmd&0x80) si = 1; else si =0; SCK = 0; cmd = cmd<<1; SCK = 1; } SCK = 0; CS = 1; } void key() { if (!key_add) { delay(15); if (!key_add) { counter++; if (counter==256) counter = 0; }while(!key_add); } if (!key_cut) { delay(15); if (!key_cut) { counter--; if (counter<0) counter = 255; }while(!key_cut); } } void main() { write_mcp4110(DATA_D0,0x90); write_8bit(CLEAR_D0); counter = 0x80; while(1) { key(); write_mcp4110(DATA_D0,counter); } }