The first and last character to be displayed in each range can be set using the al and cl 8-bit registers before calling the sub-routine.
Code:
program display_chars;
#include( "stdlib.hhf" )
// Phil Gardner
procedure displayCharRange; @noframe; @nodisplay;
begin displayCharRange;
keepDisplaying:
stdout.put( ( type char al ), " " );
inc( al );
cmp( al, cl );
jle keepDisplaying;
ret();
end displayCharRange;
// - - - - -
begin display_chars;
// Display all upper-case letters
mov( $41, al );
mov( $5A, cl );call displayCharRange;
stdout.put( nl );
// Display all lower-case letters
mov( $61, al );
mov( $7A, cl );call displayCharRange;
stdout.put( nl );
// Display all numeric digits
mov( $30, al );
mov( $39, cl );call displayCharRange;
stdout.put( nl );
// Display punctuation symbols
mov( $21, al );
mov( $2F, cl );call displayCharRange;
mov( $3A, al );
mov( $40, cl );call displayCharRange;
mov( $5B, al );
mov( $60, cl );call displayCharRange;
mov( $7B, al );
mov( $7E, cl );call displayCharRange;
stdout.put( nl );
end display_chars;
