16c554.txt

本程序包含c与ASM格式的16C554的程序

#define  ST_RHR     (*(volatile unsigned char *)0x0800)   
#define  ST_THR     (*(volatile unsigned char *)0x0800)   
#define  ST_IER     (*(volatile unsigned char *)0x0900)   
#define  ST_ISR     (*(volatile unsigned char *)0x0A00)   
#define  ST_FCR     (*(volatile unsigned char *)0x0A00)   
#define  ST_LCR     (*(volatile unsigned char *)0x0B00)   
#define  ST_MCR     (*(volatile unsigned char *)0x0C00)   
#define  ST_LSR     (*(volatile unsigned char *)0x0D00)   
#define  ST_MSR     (*(volatile unsigned char *)0x0E00)   
#define  ST_SPR     (*(volatile unsigned char *)0x0F00)   
#define  ST_DLL     (*(volatile unsigned char *)0x0800)   
#define  ST_DLM     (*(volatile unsigned char *)0x0900)   

unsigned char tm_recv,tm_send;
// External Interrupt 0 service routine

void int0_isr(void)
{
// Place your code here
  if(ST_LSR & 0x01)   
      tm_recv = ST_RHR;
  if(ST_LSR & 0x40)     
      ST_THR = tm_send;     
  
}

// External Interrupt 1 service routine

void int1_isr(void)
{
// Place your code here
    if(ST_LSR & 0x01)     
      tm_recv=ST_RHR;
  if(ST_LSR & 0x40)    
      ST_THR=tm_send;   
}

// External Interrupt 2 service routine

void int2_isr(void)
{
// Place your code here
   if(ST_LSR & 0x01)    
      tm_recv=ST_RHR;
  if(ST_LSR & 0x40)     
      ST_THR=tm_send;   
}

void int3_isr(void)
{
// Place your code here
   if(ST_LSR & 0x01)    
      tm_recv=ST_RHR;
  if(ST_LSR & 0x40)     
      ST_THR=tm_send;   
}

void reset_554(void)
{                  
 PORTC &= ~0x80;     //RST=0
 delay(100);
 PORTC |= 0x80;     //RST=1
 delay(80);
 PORTC &=~0x80;     //RST=0
 delay(100);                
 
}
 

void ST16c554_init(void)
{
 reset_554();           
 ST_LCR=0x80;          
 ST_DLL=0x0C;         
 ST_DLM=0x00;          
 ST_LCR=0x03;           
 ST_FCR=0x00;           
 ST_MCR=0x02;           
 ST_IER=0x03;           
 ST_SPR=0xAA;          
}   




汇编：8086

INIMODEM：
MOV DPTR，#0F803H ；DPTR 指向线控寄存器LCR
MOV A，#80H       
MOVX @DPTR，A     ；置DLAB=1，设置波特率 
ANL DPL，#0F8H
MOV A，#0CH
MOVX @DPTR，A     ；送波特率常数：9600baud
INC DPL
CLR A
MOVX @DPTR，A
INC DPL
INC DPL           ；DPTR 指向线控寄存器LCR
MOV A，#03H
MOVX @DPTR，A     ；设置数据帧格式，8位数据，无校验位，1位停止位
INC DPL           ；指向MODEM控制寄存器
MOV A，#01H
MOVX @DPTR，A     ；置设备终端准备就绪
ANL DPL，#0F8H
ORL DPL，#02H     ；指向MODEM控制寄存器MCR
MOV A，#03H       ；置FIFO 有效，清接收FIFO
ANL DPL，#0F08H
ORL DPL，#01H     ；DPTR 指向中断允许寄存器IER
MOV A，#01H
MOVX @DPTR，A     ；设置接收寄存器中有数则中断
RET