;---------------------------------------------------------------------------------
; Useful defines, equates and macros:
;---------------------------------------------------------------------------------
; Register aliases:
.def	nul	= r2		; Zero (0x00) value register - must be cleared in init
.def	one	= r3		; One (0x01) value register - must be initialized to 1 in init
.def	stsav	= r4		; SREG save register
.def	tmp	= r16		; Temporary register
.def	tmp2	= r17		; Temporary register 2

; Constant equates:
.equ	fosc	= 16000000	; Clock oscillator frequency, Hz
.equ	mips	= fosc/1000000	; MIPS
.equ	baud	= 9600		; Baud rate, Baud - useful for delay subroutines
.equ	brrval	= (fosc/(16*baud))-1	; Calculated UBRR value - no need to do it manually

; Literal substitutes:
#define	@	1<<		; Now (@ foo) can be used instead of (1 << foo)

;---------------------------------------------------------------------------------
.macro	ldiw
; Writes a 16-bit immediate value to a 16-bit xyzH/xyzL register pair.
; Usage: ldiw X[or Y, or Z],value.
	ldi	@0H,high(@1)
	ldi	@0L,low(@1)
.endm
;.................................................................................

.macro	outi
; Writes a 8-bit immediate value to an 8-bit i/o SFR.
; Usage: outi IOREG8,value.
; Uses/trashes a tmp register for operation.
	ldi	tmp,@1
	out	@0,tmp
.endm
;.................................................................................

.macro	outiw
; Writes a 16-bit immediate value to a 16-bit xxxH/xxxL i/o SFR pair.
; Usage: outiw IOREG16,value.
; Uses/trashes a tmp register for operation.
	ldi	tmp,high(@1)	; @1 = second macro argument,
	out	@0H,tmp	; @0 = first macro argument.
	ldi	tmp,low(@1)	; Up to 10 macro arguments can be used (@0...@9)
	out	@0L,tmp	; H/L is appended to an argument literally
.endm
;.................................................................................

.macro	adi
; Adds 8-bit immediare value to a high register
; Usage: adi r16{or r17...r31],value
	subi	@0,-@1
.endm
;.................................................................................

.macro	adci
; Adds 8-bit immediare value and carry to a high register
; Usage: adci r16{or r17...r31],value
	sbci	@0,-@1
.endm
;.................................................................................

.macro	addiw
; Adds 16-bit immediare value to a L/H named register pair
; Usage: addiw W[or X, Y, Z],value
	subi	@0L,low(-@1)
	sbci	@0H,high(-@1)
.endm
;.................................................................................

;---------------------------------------------------------------------------------
; Usage examples:
msg1:
	.db	"This is a message"
Code:
	clr	nul		; Initialize zero (0x00) holding byte register
	clr	nul		; Initialize constant (0x01) holder byte register

	ldiw	z,msg1*2	; Load a msg1 BYTE address to ZH:ZL
	outi	UBRR,brrval	; Load a 8-bit i/o register with immediate 8-bit value
	outi	ADMUX,(@ REFS0)|(@ ADLAR)|(4<<MUX0)	; Example: ADC setup: Vref = int, left adjust, ADC input = PINA4
	outiw	SP,RAMEND	; Load a 16-bit i/o register with immediate 16-bit value
	adi	temp,0xAB	; Add 8-bit immediate to an 8-bit register
	adci	temp2,0xCD	; Add 8-bit immediate to an 8-bit register with carry
	addiw	x,0x1234	; Add 16-bit immediate to a 16-bit register pair (XH:XL, YH:YL, ZH:ZL)

	add	xl,temp		; Add 8-bit register to 16-bit register pair (XH:XL = XH:XL + temp)
	adc	xh,nul		;

	cp	r0,one		; Compare an 8-bit register to "1"

ISRexample:
	in	stsav,SR	; Save Status Register
	; Your ISR code goes here
	out	SR,stsav	; Restore Status Register
	reti
;---------------------------------------------------------------------------------