// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *  
// BV4218 LCD + Keypad circuit board
// the same routines can be used for the BV4208 LCD, IC and
// the BV4207 keypad chip. 
// This is a simple demonstration thst will check the keypad and 
// then add 2 numbers together. It has been designed for a 2 x 16 line
// display  but should work with lareger displays.
// The technique used here is to extend the BV4218 library with a SID
// of 102 and then only make the wotd GO public.
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *  

// REQUIRES:
// #URL-lib "http://pin1.org/forthlib/flb/General/soft1.flb"
// #URL-lib "http://pin1.org/forthlib/flb/General/pinsel.flb" sid=100
// #URL-Lib "http://pin1.org/forthlib/flb/I2C/i2c.flb" sid=101
// #URL-inc "http://pin1.org/forthlib/flb/I2C/BV4218.flb" sid=102

// CONSTANTS:
//  none

// extend BV4218 library
// #currentSID sid=102

: l2-d l2 5 ms ; // this display requires a delay afet moving cursor
: lh-d lh 5 ms ; // 
: l2n ( n -- ) &c0 + LCDcmd 5 ms ; // moves curse on second line to position n
: msg1 s" BV4128 Demo" stype2 ;
: msg2 s" Display & Keypad" stype2 ;
: msg3 s" Enter 2 values" stype2 ;
: msg4 s" # is enter key" stype2 ;

// wait here for a key press and return with key that
// was pressed
: key-wait ( -- k )
  begin
    key? abort" terminal key pressed"
    kn  // goes to <>0 when keypad pressed
    1 ms  // dont overload i2c
  until
  kg    // get gey from keypad  
;

// checks to see if keypad has been set up, # key should
// be value 11. Returns true if it is.  
: keypadset? ( -- -1|0 )
  lc s" Press the # key" stype2
  kc  // clear key buffer
  key-wait
  11 =
;    

// asks the user to press the hash key that has been set a value of
// 11, if it does not return 11 then it goes through the kepad setup
: setkeypad
  keypadset? invert
  if
    lc s" keys need seting" // no room for another t
    1000 ms
    key-map-l
  then 
;    

// gets a decimal number form the keypad, terminated with the
// # key, echoes number to display
: get-number ( -- n )
  0     // start with 0
  begin
    key-wait  // get value pressed
    dup 11 = if drop escape then // enter key
    dup ln    // echo
    swap 10 *    // multiply existing by position
    +         // add to existing
  again
;    

// sign on to display, tell user whats gong on and set up the lcd
// NOTE version k firmware onwards has command 55 so that a sucessfull
// conection to the device can be established, this assumes an older version.
: signon
  66 lcd-init    // set i2c bus
  0 blight    // trun on back light if there is one
  lc msg1 l2-d msg2  // sign on
  2000 ms
;

// this is the public word
: <0>go
  signon
  setkeypad   // check keypad is set up
  lc msg3 l2-d msg4 2000 ms // user instructions
  // get keys and calculate sum
  lc s" First Value" stype2 
  l2-d s" * " stype2 get-number // on stack
  // get second number
  lh-d  // home cursor but dont clear display
  s" Second Value" stype2 
  6 l2n  // second line 6th position
  s" * " stype2 get-number  // get second number
  12 l2n 
  s" = " stype2 + ln  
;

// #currentSID sid=102
// back to default SID