>      I am having a very diffictult time getting an at89c2051 to send characters to a PC via the serial port.  I'm using a MAX235 (no ext components), as the RS232 driver.
>      The problem is, the PC doesn't recognize anything the 89c2051 sends out (not even garbage).  I've used a logic probe to verify data is actually being sent and appears on the RS232 side of the MAX235.
>      I've tested the PC port by connecting TX to RX going through the MAX235, and it checks out OK.  The distance from the 89c2051 to the PC is only about a foot, so I don't think the line length is the problem.
>      I'm pretty much stumped at this point and would appreciate any pointers, advice, etc.
>
>      Below is the program I'm using (P1_7 is used to blink an LED so that I know it's running).
>
> #include <at89x2051.h>
>
> //#define BAUD 19200
> //#define RELOAD 253    //19200
> #define RELOAD 192    //300
> //#define RELOAD 250 //9600
>
> void main(){
>    int x,j;
>
>    TCON=0;
>    TH1=RELOAD;
>    TMOD=32;   //Timer 1=8 bit auto reload
>    PCON=128; //Double baud rate
>    //PCON=0; //don't Double baud rate
>    SCON=64; //Enable serial
>    TR1=1;
>    P1_7=0;
>
>    while(1){
>       for(j=0;j<5;j++){
>          TI=0;
>          SBUF='A';
>          while(TI==1){}
>          for(x=0;x<10000;x++){}
>       }
>       TH1--;
>       if(P1_7==0){
>          P1_7=1;
>       } else {
>          P1_7=0;
>       }
>    }
> }
>
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