- function ascii2sc (x : hbyte) return hbyte is
- variable y : hbyte;
- begin
- case x is
- when x"30" => y := SC_KP_0;
- when x"31" => y := SC_KP_1;
- when x"32" => y := SC_KP_2;
- when x"33" => y := SC_KP_3;
- when x"34" => y := SC_KP_4;
- when x"35" => y := SC_KP_5;
- when x"36" => y := SC_KP_6;
- when x"37" => y := SC_KP_7;
- when x"38" => y := SC_KP_8;
- when x"39" => y := SC_KP_9;
- when x"2b" => y := SC_KP_PLUS;
- when x"2d" => y := SC_KP_MINUS;
- when x"2a" => y := SC_KP_MUL;
- when x"2f" => y := SC_KP_DIV;
- when x"20" => y := SC_SPACE;
- when x"1c" => y := SC_ENTER;
- when x"0e" => y := SC_BKSP;
- when others => y := x"41";
- end case;
- return y;
- end function;
-
- function valid_char (x : std_logic_vector(7 downto 0)) return boolean is
- variable y : boolean;
- begin
- case x is
- when SC_KP_0 | SC_KP_1 | SC_KP_2 | SC_KP_3 |
- SC_KP_4 | SC_KP_5 | SC_KP_6 | SC_KP_7 |
- SC_KP_8 | SC_KP_9 | SC_KP_PLUS |
- SC_KP_MINUS | SC_KP_MUL |
- SC_KP_DIV | SC_SPACE |
- SC_BKSP | SC_ENTER =>
- y := true;
- when others => y := false;
- end case;
- return y;
- end function;
-