protocol.c

16C554VX1128MAX4359-MAX4456P89LPC952 驱动开发

#include <REG952.H>
#include <intrins.H>
#include "16C554.h"
#include "video_matrix.h"
#include "com_proto.h"
#include "uart.h"
#include "wdt.h"

extern cmdflag,cmdpos;
//*************************************************************************
//函数名: protocol
//功 能: 串口协议,实现串口扩展和视频矩阵切换
//入参数: cmd 为从串口得到的一个字符
//出参数: 无
//*************************************************************************
void protocol(unsigned char cmd)
{
	uchar cmdlen,i,a,check_sum=0,command[SIZE];
	uint *temp;
	if(cmdflag == 0)
	{
		cmdpos = 0;
		if(cmd == COM_START_CODE)
		cmdflag = 1;	
	} 
	else 
	{
		command[cmdpos++] = cmd;
		if(cmdpos < SIZE)		//表明数组没有溢出
		{
			if(cmdpos == command[0])  //即一串数据传送完毕
			{ 	
				cmdlen = command[0];
				for(i=4;i<cmdlen;i++)
				{
					check_sum += command[i-1];	
				}
				temp = (unsigned int*)&command[1];
				if(command[i-1] == check_sum)
				{
					switch(*temp)		//为0003则为CMD_SwitchVideo	为0005则为CMD_UartData
					{
						case CMD_SwitchVideo:
						{
					    	matrix_write(command[3],command[4]);	  //对matrix进行输入输出配置或
							matrix_write(command[5],command[4]);	  //命令配置
							cmdflag = 0;
						}						
						break;
		
						case CMD_UartData:
						{
							uint j;
							SC16C554_Write(command[3]|LCR,0x80);  //设置UART1 波特率
	   						SC16C554_Write(command[3]|DLL,DLL_DATA); //设置DLL 低位
	    					SC16C554_Write(command[3]|DLM,DLM_DATA); //设置DLL 高位
	    					SC16C554_Write(command[3]|LCR,0x03);  //8位数据,1 位停止位,无奇偶校验位
	    					SC16C554_Write(command[3]|FCR,0x07);  //允许并复位FIFO
							 
							SC16C554_Write(command[3]|IER,0x00);  //设置16C554禁止所有中断
//							SC16C554_Write(command[3]|IER,0x02); 	//允许554发送终止中断Enable the transmitter empty interrupt
							SC16C554_Write(command[3]|MCR,0x08);	//打开554串口总开关	
							for(j=4;j<=cmdlen-2;j++)	//从要选择的串口发送内容:从
							{
								a=SC16C554_Read(command[3]|LSR);
								while(!a&(0x1<<5));   //等待THR空
								SC16C554_Write(command[3]|THR, command[j]);  //发送数据			
	       	 				} 						
							cmdflag = 0;
						}
						break;
						default:
						{
							cmdflag = 0;	
						} 
					}
				}
				else 	//若输入数据有错误
				{
					cmdflag = 0;
				}	
			}
		}
		else 	//数组溢出
		{
			cmdflag = 0;
		}		
	}	
}