按TAB跳过操作？

Question

我想知道当程序启动时用户可以输入他的坐标的可能性，并且他可以通过按<TAB>跳过这一段。当你点击程序时，程序应该进行随机坐标检查，即直到(ch = $ 9)的成本。但它对我不起作用。请告诉我，我该如何修复代码？

    uses crt, graphabc;
var
  x,y: array[1..16] of real;
  s:array[1..16] of char;
  i,p,t,w,f,c:integer;
  z:string;
const
  a=14;
  b=29;
  r=27;
  procedure ReadKey(ch : char);
begin
 SetWindowSize(840, 600);
  randomize;
  t:=0;
  w:=10;
  f:=0;

Coordinate.Origin:=new Point(20,120);
  for i:=1 to 15 do 
      begin
 if i=1 then
    begin
    if (ch = $9) then begin
    Coordinate.Origin:=new Point(0,0);
    line(8, 8, 260, 8);
    line(8, 30, 260, 30);
    line(8, 8, 8, 30);
    line(260, 8, 260, 30);
    TextOut(15, 10, 'Enter your coordinates through a space');
    Coordinate.Origin:=new Point(10,110);
    readln(x[1],y[1]);
    end;

    until(ch = $9);

    end;
        s[i]:=chr(64+i);
        x[i+1]:=(-30+(34+30)*random);
        y[i+1]:=(-35+(34+35)*random);
        writeln(s[i],'(', x[i]:3:0, ';',y[i]:3:0,')');
        if (x[i]*x[i]+y[i]*y[i]<=r*r) and (x[i]>=0) or
           (x[i]*x[i]+y[i]*y[i]<=r*r) and (x[i]<=-4) or
           (x[i]*x[i]+y[i]*y[i]<=r*r) and (x[i]<=0) and (y[i]<=round(-b/2)) or
           (x[i]*x[i]+y[i]*y[i]<=r*r) and (x[i]<=0) and (y[i]<=round(b/2))
        then t:=t+1;
        if (x[i]*x[i]+y[i]*y[i]>r*r) then begin 
           TextOut(65, f, ' - point outside the boundary of a circle');
           f:=f+16;
        end
           else if (x[i]*x[i]+y[i]*y[i]=r*r) then begin 
              TextOut(65, f, ' - the point hit the outer border');
              f:=f+16; 
           end
           else if (x[i]*x[i]+y[i]*y[i]<=r*r) and (x[i]>=0) or
                   (x[i]*x[i]+y[i]*y[i]<=r*r) and (x[i]<-14) or
                   (x[i]*x[i]+y[i]*y[i]<=r*r) and (x[i]<=0) and (y[i]<round(-b/2)) or
                   (x[i]*x[i]+y[i]*y[i]<=r*r) and (x[i]<=0) and (y[i]=round(b/2))
                   then begin
                        TextOut(65, f, ' - the point hit the inner border');
                        f:=f+16;
                        end
                   else begin
                        TextOut(65, f, ' - the point fell outside the internal border');
                        f:=f+16;
                        end
         end;