# 18fxx2 microcontroller target compiler


# the target is an (incremental optimizing) procedure threaded
# forth (native code), using 2 dictionaries: words & macros,
# in the style of colorforth.

(bitgrid 16 0x1000) new constant pic-buf
0x100 variable! pic-ast

: pic-comma pic-ast >r r ! r> 1 + pic-ast ! ;
: pic-here pic-ast @ ;


# load assembler defines
"18f452-defs.pf" load

# load instruction set
"18fxx2-ins.pf" load


() variable! pic-word
() variable! pic-macro



# assembler
: w| ;			# destination wreg DEFAULT
: reg| 0x0200 or	# destination freg
: op| 0xff and or ;	# add operand to instruction
: xop| swap op| ;

# 0-op macro instructions ( -- opcode )
: DROP MOVF  POSTDEC0 op| w| ;
: DUP  MOVWF PREINC0 op| reg| ;

# 1-op macro instructions ( thing -- opcode )
: LIT  MOVLW xop| ;


# symbolic forth stuff
: pic-find-macro pic-macro @find @ ;
: pic-find-word pic-word @find @ ;

: pic-literal 
	` lit pic-find pic-compile
	int pic-comma ;