fsearch.asm

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.nolist
.include	"param.inc"
.list

	.comm fileID, 2
	.bitcomm fastI2C, 1

	.text

.global	searchfile
searchfile:
;r4	file type
;dptr	file start
;r2r3	file end
.ifdef I2Cfilesystem
	jnb	I2Cpresent,L_NoScanI2C
	clr	fastI2C
	mov	dptr,#4		;offset of "file directory" in I2C EEPROM
L_I2Cdir: lcall	read_random
	inc	a	;end of directory ?
	jz	L_I2Ceof
	dec	a
	xrl	a,fileID
	jnz	L_nextI2Cdir
	lcall	read_current
	xrl	a,fileID+1
	jnz	L_nextI2Cdir
	lcall	read_current
	mov	r4,a	;file type
	lcall	read_current
			;reserved
	lcall	read_current
	mov	dph,a	;MSB file start
	lcall	read_current
	mov	dpl,a	;LSB file start
	lcall	read_current
	mov	r2,a	;MSB file end
	lcall	read_current
	mov	r3,a	;LSB file end
	mov	r5,#0	;I2C filesystem
	clr	c	;O.K.
	ret
L_nextI2Cdir:
	mov	a,dpl
	add	a,#8
	mov	dpl,a
	jnc	L_I2Cdir
	inc	dph
	sjmp	L_I2Cdir
L_I2Ceof:
L_NoScanI2C:
.endif
.ifdef ROMfilesystem
	mov	dptr,#filedir	;offset of "file directory" in ROM
L_ROMdir: clr	a
	movc	a,@a+dptr
	inc	a	;end of directory ?
	jz	L_ROMeof
	dec	a
	xrl	a,fileID
	jnz	L_nextROMdir
	mov	a,#1
	movc	a,@a+dptr
	xrl	a,fileID+1
	jnz	L_nextROMdir
	mov	a,#2
	movc	a,@a+dptr
	mov	r4,a	;file type
	mov	a,#6
	movc	a,@a+dptr
	mov	r2,a	;MSB file end
	mov	a,#7
	movc	a,@a+dptr
	mov	r3,a	;LSB file end
	mov	a,#4
	movc	a,@a+dptr
	push	acc	;MSB file start
	mov	a,#5
	movc	a,@a+dptr
	mov	dpl,a	;LSB file start
	pop	dph	;MSB file start
	mov	r5,#1	;ROM filesystem
	clr	c	;O.K.
	ret
L_nextROMdir:
	mov	a,dpl
	add	a,#8
	mov	dpl,a
	jnc	L_ROMdir
	inc	dph
	sjmp	L_ROMdir
L_ROMeof:
.endif
.ifdef EEfilesystem
	mov	dptr,#fileee	;offset of "file directory" in EEPROM
	ENABLE_EE
L_EEdir: clr	a
	movx	a,@dptr
	inc	a	;end of directory ?
	jz	L_EEeof
	dec	a
	xrl	a,fileID
	jnz	L_nextEEdir
	inc	dptr	;1
	movx	a,@dptr
	xrl	a,fileID+1
	jnz	L_nextEEdir7
	inc	dptr	;2
	movx	a,@dptr
	mov	r4,a	;file type
	inc	dptr	;3
	inc	dptr	;4
	movx	a,@dptr
	push	acc	;MSB file start
	inc	dptr	;5
	movx	a,@dptr
	push	acc	;LSB file start
	inc	dptr	;6
	movx	a,@dptr
	mov	r2,a	;MSB file end
	inc	dptr	;7
	movx	a,@dptr
	mov	r3,a	;LSB file end
	pop	dpl	;LSB file start
	pop	dph	;MSB file start
	clr	c	;O.K.
	DISABLE_EE
	mov	r5,#2	;EEPROM filesystem
	ret
L_nextEEdir:
	inc	dptr
L_nextEEdir7:
	mov	a,dpl
	add	a,#7
	mov	dpl,a
	jnc	L_EEdir
	inc	dph
	sjmp	L_EEdir
L_EEeof:
	DISABLE_EE
.endif
	setb	c	;file not found
	ret
;
	;; END