// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *  
// BV4219 Graphic display
// This is a library of words inteded for this device it is an I2C
// device. The user should set the device address
// using the word 4219-init and supplying a device address.
// This will load as a stand alone file or can be used as a library
// providing the parent file includes the files in the REQUIRES 
// section
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *  

// REQUIRES:
// #URL-lib "http://pin1.org/forthlib/flb/General/soft1.flb" sid=0
// #URL-lib "http://pin1.org/forthlib/flb/General/pinsel.flb" sid=101
// #URL-Lib "http://pin1.org/forthlib/flb/I2C/i2c.flb" sid=103

// CONSTANTS:
// This variable is used to hold the I2C address of the device
// it can be chaned to a constant if required.
integer device 

// These are simple commands following the device commands. 
: a1 ( on/off -- ) device s 1 sb sb p ;  // turn display on or off, 1=on
: a2 ( -- cmd ) device s 2 sb sb p ; // sends command to display
: a3 ( -- byte ) device s 3 sb sb p ; // write byte
: a4 { bytes -- } device s 4 sb // reads bytes on display 
    device 1+ rs
    bytes 1- for
        rn 
    next
    rl
    p ;  
: a6 ( 1|0 -- ) device s 6 sb sb p ; // back light on/off      
: a5 ( -- ) device s 5 sb p ; // reset
: a7 ( x -- ) device s 7 sb sb p ; // set x position
: a8 ( r -- ) device s 8 sb sb p ; // set r position
: a9 { x r b -- } device s 9 sb x sb r sb b sb p ; // plce byte 
: aa { x y b -- } device s &a sb x sb y sb b sb p ; // plce byte 
: a10 ( byte -- ) device s &10 sb sb p ; // fills display with byte
: pixon { x y -- } // on is white
    device s &11 sb x sb y sb 1 sb p ; // turns on pixel    
: pixoff { x y -- } // on is white
    device s &11 sb x sb y sb 0 sb p ; // turns on pixel    
: dhl { x y l -- } 
  device s &12 sb x sb y sb l sb p ;  // draw horizontal line 
: dhli { x y l -- } 
  device s &13 sb x sb y sb l sb p ; // draw horizontal line 
: dvl { x y l -- } 
  device s &14 sb x sb y sb l sb p ;  // draw veritcal line
: dvli { x y l -- } 
  device s &15 sb x sb y sb l sb p ; // draw veritcal line
: dbnf { x y xl yl -- } 
    device s &16 sb x sb y sb xl sb yl sb p ; // draw box no fill 
: dbwf { x y xl yl -- } 
    device s &18 sb x sb y sb xl sb yl sb p ; // draw box with fill 
: a20 ( char -- ) device s &20 sb sb p ; // send white character
: a21 ( char -- ) device s &21 sb sb p ; // send dark character
: a22 ( udf -- ) device s &22 sb sb p ; // send white udf from eeprom
: a23 ( udf -- ) device s &23 sb sb p ; // send dark udf from eeprom
: a25 { r c  -- } device s &25 sb r sb c sb p ; // text cursor position 
: a27 ( -- x ) device s &27 sb device 1+ rs rl p ; // gets x pos
: a28 ( -- r ) device s &28 sb device 1+ rs rl p ; // gest r pos

// send string to text terminated with 0, do not exceed 32 charaters
: send-text { addr --- }
  device s &20 sb   // device and command
  begin
    addr c@ 0 <>
  while
    addr c@ sb
    1 +> addr
  repeat
  p     // stop
;  
// a55 will test if device is working and return t/f
: a55 ( -- t/f ) device s &55 sb device 1+ rs rn 1 = rn 2 = and rl 3 = and p ;

// read eeprom
// # number of bytes to read and 
// from is starting address of eeprom
: a90 ( #, from -- values ) 
  device s &90 sb sb device 1+ rs 
  1- for rn next 
  rl p ;
  
// write all of the byts that are on the stack to eerpm
// starting at address start. Note start has to be last value on stack
: a91 ( [ .. ] start -- )
  device s &91 sb sb
  depth for sb next
  p ;
  
: a93 ( -- x ) device s &93 sb device 1+ rs rl p ; // end of eerpom  
: a94 ( -- ) device s &94 sb p ; // sleep
: a95 ( -- ) device s &95 sb p ; // reset
: a96 ( -- ) device s &96 sb &55 sb &aa sb p ; // restore factory defaults
// imediately sets new i2c address to eeprom
: a99 ( new -- ) device s &99 sb dup sb &55 sb &aa sb device sb => device p ;
: aa0 ( -- ver. ) device s &a0 sb device 1+ rs
        rn . ." ." rl emit p ;

// use this first to establish i2C address if device and
// to initialise i2c system with default speed, if sucess requirn -1
: 4219-init ( device -- -1|0 ) => device i2-init a55 ;
: i2cslow ( -- ) 100000 i2speed ; // sets i2c to slow speed
: i2cfull ( -- ) 400000 i2speed ; // sets i2c to full speed  
: 4219-default 66 4219-init i2cfull ;