-- Title: seven_segment.jal - translation routine for 7 segment display
-- Author: Wouter van Ooijen (c) 1998, all rights reserved.
-- Adapted-by: Joep Suijs, Vasile Surducan 25.08.2009
-- Compiler: >=2.2
-- 
-- This file is part of jallib (http://jallib.googlecode.com)
-- Released under the ZLIB license (http://www.opensource.org/licenses/zlib-license.html)
--
-- Sources: 
-- 
-- Description:  Translation routine for 7 segment display. 
-- --                                                             
-- The seven segment display needs to be connected to a single port.
-- Define the pin layout of the seven segment display like:
--           _a_
--         /    /
--        f    b
--       /    /
--       _g_
--     /    /
--    e    c
--   /    /
--   _d_
--
-- -- constant for the segments      gfe dcba
-- const byte seven_segment_a  = 0b_0000_0001
-- const byte seven_segment_b  = 0b_0000_0010
-- const byte seven_segment_c  = 0b_0000_0100
-- const byte seven_segment_d  = 0b_0000_1000
-- const byte seven_segment_e  = 0b_0001_0000
-- const byte seven_segment_f  = 0b_0010_0000
-- const byte seven_segment_g  = 0b_0100_0000
-- const byte seven_segment_dp = 0b_1000_0000   
-- --
-- character set:
-- --
-- value 0 is character "0"
-- value 1 is character "1"
-- value 2 is character "2"
-- value 3 is character "3"
-- value 4 is character "4"
-- value 5 is character "5"
-- value 6 is character "6"
-- value 7 is character "7"
-- value 8 is character "8"
-- value 9 is character "9"
-- value 10 is character "A"
-- value 11 is character "b"
-- value 12 is character "C"
-- value 13 is character "d"
-- value 14 is character "E"
-- value 15 is character "F"
-- value 16 is character "S"
-- value 17 is character "c"
-- value 18 is character "r"
-- value 19 is character "H"
-- value 20 is character "i"
-- value 21 is character "L"
-- value 22 is character "o"
-- value 23 is character "P"
-- value 24 is character "U"
-- value 26 is character "u"
-- value 27 is character "space"
-- value 28 is character "J"
-- value 29 is character "n"
-- value 30 is character "h"
-- value 31 is character "celsius degree"
-- value 32 is character "_"
-- value 33 is character "="
-- value 34 is character "-"
-- value 35 is character "segment dp" (DOT)
-- --
-- Use:  
-- --
-- const bit seven_segment_common_anode = true ; omit this line if you use a common cathode display.
-- --
-- portd_direction = all_output
-- portd = seven_from_digit(1) -- display '1'
-- --    
--
-- Notes: 
--


if (defined(seven_segment_common_anode) == false) then
   const bit seven_segment_common_anode = false -- default is common_cathode
end if


if (seven_segment_common_anode == true) then
   const _seven_common_mask = 0xff
else
   const _seven_common_mask = 0x00
end if


if (defined(seven_segment_a) == false) then   
   -- Default segment setup          gfe dcba
   const byte seven_segment_a  = 0b_0000_0001
   const byte seven_segment_b  = 0b_0000_0010
   const byte seven_segment_c  = 0b_0000_0100
   const byte seven_segment_d  = 0b_0000_1000
   const byte seven_segment_e  = 0b_0001_0000
   const byte seven_segment_f  = 0b_0010_0000
   const byte seven_segment_g  = 0b_0100_0000
   const byte seven_segment_dp = 0b_1000_0000
   
end if

const byte seven_value_space[] = {
   -- value 0 is character "0"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_b  
   + seven_segment_c  
   + seven_segment_d
   + seven_segment_e
   + seven_segment_f       ),
   
   -- value 1 is character "1"
   _seven_common_mask ^ (
     seven_segment_b  
   + seven_segment_c    ),
   
   -- value 2 is character "2"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_b  
   + seven_segment_d
   + seven_segment_e
   + seven_segment_g    ),
   
   -- value 3 is character "3"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_b  
   + seven_segment_c  
   + seven_segment_d
   + seven_segment_g    ),
   
   -- value 4 is character "4"
   _seven_common_mask ^ (
     seven_segment_b  
   + seven_segment_c  
   + seven_segment_f
   + seven_segment_g    ),
   
   -- value 5 is character "5"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_c  
   + seven_segment_d
   + seven_segment_f
   + seven_segment_g    ),
   
   -- value 6 is character "6"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_c  
   + seven_segment_d
   + seven_segment_e
   + seven_segment_f
   + seven_segment_g    ),
   
   -- value 7 is character "7"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_b  
   + seven_segment_c    ),
   
   -- value 8 is character "8"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_b  
   + seven_segment_c  
   + seven_segment_d
   + seven_segment_e
   + seven_segment_f
   + seven_segment_g    ),
   
   -- value 9 is character "9"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_b  
   + seven_segment_c  
   + seven_segment_d
   + seven_segment_f
   + seven_segment_g    ),
   
   -- value 10 is character "A"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_b  
   + seven_segment_c  
   + seven_segment_e
   + seven_segment_f
   + seven_segment_g    ),
   
   -- value 11 is character "b"
   _seven_common_mask ^ (
     seven_segment_c  
   + seven_segment_d
   + seven_segment_e
   + seven_segment_f
   + seven_segment_g    ),
   
   -- value 12 is character "C"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_d
   + seven_segment_e
   + seven_segment_f    ),
   
   -- value 13 is character "d"
   _seven_common_mask ^ (
     seven_segment_b  
   + seven_segment_c  
   + seven_segment_d
   + seven_segment_e
   + seven_segment_g    ),
   
   -- value 14 is character "E"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_d
   + seven_segment_e
   + seven_segment_f
   + seven_segment_g    ),
   
   -- value 15 is character "F"
   _seven_common_mask ^ (
     seven_segment_a   
   + seven_segment_e
   + seven_segment_f  
   + seven_segment_g    ),
   
   -- value 16 is character "S"
   _seven_common_mask ^ (
     seven_segment_a
   + seven_segment_f
   + seven_segment_g  
   + seven_segment_c
   + seven_segment_d    ),
   
   -- value 17 is character "c"
   _seven_common_mask ^ (
     seven_segment_g
   + seven_segment_e
   + seven_segment_d    ),
   
   -- value 18 is character "r"
   _seven_common_mask ^ (
     seven_segment_g
   + seven_segment_e    ),
   
   -- value 19 is character "H"
   _seven_common_mask ^ (
     seven_segment_f
   + seven_segment_e
   + seven_segment_g
   + seven_segment_b
   + seven_segment_c    ),
   
   -- value 20 is character "i"
   _seven_common_mask ^ (
     seven_segment_c    ),
   
   -- value 21 is character "L"
   _seven_common_mask ^ (
     seven_segment_f
   + seven_segment_e
   + seven_segment_d    ),
   
   -- value 22 is character "o"
   _seven_common_mask ^ (
     seven_segment_g
   + seven_segment_c
   + seven_segment_d
   + seven_segment_e    ),
   
   -- value 23 is character "P"
   _seven_common_mask ^ (
     seven_segment_a
   + seven_segment_b
   + seven_segment_g
   + seven_segment_f
   + seven_segment_e    ),
   
   -- value 24 is character "U"
   _seven_common_mask ^ (
     seven_segment_f
   + seven_segment_e
   + seven_segment_d
   + seven_segment_c
   + seven_segment_b    ),

   -- value 25 is character ??? <-- this is an omission
   _seven_common_mask ^ (
     seven_segment_f
   + seven_segment_e
   + seven_segment_d
   + seven_segment_c
   + seven_segment_b    ),

   -- value 26 is character "u"
   _seven_common_mask ^ (
     seven_segment_e
   + seven_segment_d
   + seven_segment_c    ),

   -- value 27 is character "space"
   _seven_common_mask ^ (
      0                 ),

   -- value 28 is character "J"
   _seven_common_mask ^ (
      seven_segment_b
    + seven_segment_c
    + seven_segment_d   ),

   -- value 29 is character "n"
   _seven_common_mask ^ (
      seven_segment_c
    + seven_segment_e
    + seven_segment_g   ),

   -- value 30 is character "h"
   _seven_common_mask ^ (
      seven_segment_c
    + seven_segment_e
    + seven_segment_f
    + seven_segment_g   ),

   -- value 31 is character "celsius degree"
   _seven_common_mask ^ (
      seven_segment_a
    + seven_segment_b
    + seven_segment_g
    + seven_segment_f   ),

   -- value 32 is character "_"
   _seven_common_mask ^ (
      seven_segment_d   ),

   -- value 33 is character "="
   _seven_common_mask ^ (
      seven_segment_d
    + seven_segment_g   ),

   -- value 34 is character "-"
   _seven_common_mask ^ (
      seven_segment_g   ),

   -- value 35 is character "." (segment DOT)
   _seven_common_mask ^ (
      seven_segment_dp  )
}

-- return seven segment value corresponding to lower nibble of x
function seven_from_digit( byte in x ) return byte is      
   
   return seven_value_space[x]
   
end function