TITLE	"demo of binary to decimal"
;		Note:  This code is seriously overcommented
;		because it is intended for those only just learning
;		about calling, receiving and return sequences.

;		Note:  This contains C code not yet translated to SMAL Hawk code

	USE	"hawk.h"
	USE	"stdio.h"

	INT	MAIN
	S	MAIN

; activation record structure holding local variables of MYDEC
				; void mydec( unsigned int i ) {
RETAD	=	0
I	=	4		;   int i, the parameter
DIGIT	=	8		;   int digit, least sig digit of i
TOP	=	12		;   int top, more sig digits of i
ARSIZE	=	16

MYDEC:				;   -- start receiving sequence for mydec
	STORES	R1,R2		;   -- save RETAD
	STORE	R3,R2,I		;   -- save and initialize I
;				    -- end receiving sequence for mydec

;				    -- start calling sequence for divideu
	LOAD	R3,R2,I		;   -- param I
	LIS	R4,10		;   -- param 10
	ADDI	R2,R2,ARSIZE	;   -- push AR for mydec
	LIL	R1,DIVIDEU
	JSRS	R1,R1		;   -- divideu( I, 10 ) gets quotient, remainder
	STORE	R3,R2,TOP	;   top = I / 10
	STORE	R4,R2,DIGIT	;   digit = I % 10
	ADDI	R2,R2,-ARSIZE	;   -- pop AR for mydec
;				    -- end calling sequence for divideu

    // C code not yet translated to SMAL HAwk assembly code
    if (top != 0) mydec( top ); // recursive call
    putchar( '0' + digit );     // regular call

;				    -- return sequence for mydec
	LOADS	PC,R2		;   return
;				    -- end return sequence for mydec

MAIN:
	STORES	R1,R2		; -- receiving sequence

				; -- calling sequence begins here
	LIL	R3,123456789	; -- pass a param
	ADDSI	R2,4		; -- push AR for main
	JSR	R1,MYDEC	; mydec( 123456789 )
	ADDSI	R2,-4		; -- pop AR for main
				; -- calling sequence ends here

	LOADS	PC,R2		; --return sequence

	END