fastload.h

供AVR的ATiny及ATmega系列单片机使用的bootloader

;*************************************************************************
.include "compat.h"	; compatibility definitions
.include "protocol.h"
;-------------------------------------------------------------------------
;				Constant definitions
;-------------------------------------------------------------------------
.equ	VERSION		= 0x0201

.equ	XTAL		= 8000000	; 8MHz, not critical 
.equ	BootDelay	= XTAL / 3	; 0.33s

;------------------------------	select UART mode -------------------------
.if SRX == STX && SRX_PORT == STX_PORT
  .equ	ONEWIRE		= 3
.else
  .equ	ONEWIRE		= 0
.endif

.equ	SRX_PIN		= SRX_PORT - 2
.equ	STX_DDR		= STX_PORT - 1

;------------------------------	select bootloader size -------------------

.ifndef	APICALL
  .ifndef	FirstBootStart
    .equ	APICALL		= 0
  .else
    .equ	APICALL		= 12
  .endif
.endif

.ifndef	CRC
  .equ	CRC		= 15
.endif

.ifndef VERIFY
  .equ	VERIFY		= 14
.endif

.ifndef	WDTRIGGER
  .equ	WDTRIGGER	= 9
.endif

.ifndef	SPH
  .equ	MinSize		= 198
.else
  .equ	MinSize		= 203
.endif

.equ	BootSize	= CRC + VERIFY + ONEWIRE + WDTRIGGER + MinSize

;------------------------------	UART delay loop value --------------------
.if CRC
  .equ	UartLoop	= 28		; UART loop time
.else
  .equ	UartLoop	= 24
.endif

;------------------------------	Bootloader fuse setting ------------------
.ifdef	FirstBootStart
  .if	(FlashEnd - FirstBootStart) >= 255	; 256 Words needed
    .equ	BootStart	= FirstBootStart
  .else
    .equ	BootStart	= SecondBootStart
  .endif
  ;----------------------------	max possible buffer size -----------------
  .set	BufferSize	= SRAM_SIZE / 2 - PAGESIZE
  .macro testpage
    .if		BootStart % BufferSize
      .set	BufferSize = BufferSize - PAGESIZE
      .if	BootStart % BufferSize
        .set    BufferSize = BufferSize - PAGESIZE
        testpage
      .endif
    .endif
  .endmacro
	testpage	; calculate Buffersize to fit into BootStart
  ;-----------------------------------------------------------------------
  .equ	UserFlash	= (2*BootStart)
  .equ	Application	= 0
.else
  .equ	BootStart	= ((FlashEnd - BootSize) / PageSize * PageSize)
  .equ	BufferSize	= PageSize
  .equ	UserFlash	= (2*BootStart - 2)
  .equ	Application	= BootStart - 1
.endif
;-------------------------------------------------------------------------
;				Using register
;-------------------------------------------------------------------------
.def	zerol		= r2
.def	zeroh		= r3
.def	baudl		= r4		; baud divider
.def	baudh		= r5
.def	crcl		= r6
.def	crch		= r7

;-------------------------------------------------------------------------
.def	appl		= r16		; rjmp to application
.def	apph		= r17
.def	polynoml	= r18		; CRC polynom 0xA001
.def	polynomh	= r19

.def	zx		= r21		; 3 byte Z pointer
.def	a0		= r22		; working registers
.def	a1		= r23
.def	twl		= r24		; wait time
.def	twh		= r25
;-------------------------------------------------------------------------
;				Using SRAM
;-------------------------------------------------------------------------
.dseg
	.org		SRAM_START
PROGBUFF:		.byte 2*BufferSize
PROGBUFFEND:
.cseg
;-------------------------------------------------------------------------
;				Macros
;-------------------------------------------------------------------------
.if ONEWIRE
  .macro	IOPortInit
	sbi	STX_PORT, SRX		; weak pullup on
	cbi	STX_DDR, SRX		; as input
  .endmacro
  .macro	TXD_0
	sbi	STX_DDR, SRX		; strong pullup = 0
  .endmacro
  .macro	TXD_1
	cbi	STX_DDR, SRX		; weak pullup = 1
  .endmacro
  .macro	SKIP_RXD_0
	sbis	SRX_PIN, SRX		; low = 1
  .endmacro
  .macro	SKIP_RXD_1
	sbic	SRX_PIN, SRX		; high = 0
  .endmacro
.else
  .macro	IOPortInit
	sbi	SRX_PORT, SRX
	sbi	STX_PORT, STX
	sbi	STX_DDR, STX
  .endmacro
  .macro	TXD_0
	cbi	STX_PORT, STX
  .endmacro
  .macro	TXD_1
	sbi	STX_PORT, STX
  .endmacro
  .macro	SKIP_RXD_0
	sbic	SRX_PIN, SRX
  .endmacro
  .macro	SKIP_RXD_1
	sbis	SRX_PIN, SRX
  .endmacro
.endif
;-------------------------------------------------------------------------