Using AND convert lower alphabets into upper ~ Assembly Programs

This Program Use AND operator to Convert lower alphabets into upper
x   y   x^y
1   0    0
0   0    0  
1   1    1
0   1    0


include irvine32.inc
.data

  alp byte ?
  msg byte "Please Enter an Alphabet to Make it in upper latter: ",0,13h,10h
  msg1 byte "In upper Latter:  ",0,13h,10h
  msg2 byte "Latter is :  ",0,13h,10h
  msg3 byte "Binary is :   ",0,13h,10h
  msg4 byte "ASCII is  : ",0,13h,10h

.code
  main proc
call clrscr
call crlf
     mov edx,offset msg
     call writestring
call crlf
call crlf
     mov edx,offset msg2
     call writestring
     mov edx,offset alp
     call readchar

     call writechar
call crlf
     mov edx,offset msg3
     call writestring
     call writebin
call crlf
     mov edx,offset msg4
     call writestring
     call writedec

call crlf
AND al,11011111b
call crlf
mov edx,offset msg1
     call writestring
call crlf
     mov edx,offset msg3
     call writestring

call writebin
call crlf
     mov edx,offset msg2
     call writestring
call writechar
call crlf
     mov edx,offset msg4
     call writestring
     call writedec

      exit
     main endp
   end main