--- a/src/external_flash.inc	Fri Feb 21 10:51:36 2020 +0100
+++ b/src/external_flash.inc	Fri Feb 28 15:45:07 2020 +0100
@@ -1,6 +1,6 @@
 ;=============================================================================
 ;
-;   File external_flash.inc                    combined next generation V3.0.1
+;   File external_flash.inc                   combined next generation V3.08.8
 ;
 ;
 ;   Copyright (c) 2011, JD Gascuel, HeinrichsWeikamp, all right reserved.
@@ -8,53 +8,141 @@
 ; HISTORY
 ;  2011-08-12 : [mH] creation
 
-; Misc
-	extern	incf_ext_flash_address_p1			; +1 for the ext_flash_address:3
-	extern	ext_flash_disable_protection		; disables write protection
-	extern	ext_flash_enable_protection			; enables  write protection
+
+; FLASH Memory Layout:
+;
+; 0x000000 - 0x1FFFFF    2 MB dive profile data, shared ring buffer
+; 0x200000 - 0x2FFFFF    1 MB dive header  data, last 256 dives, 4 kB / dive
+; 0x300000 - 0x3DFFFF  896 kB unused
+; 0x3E0000 - 0x3DFFFF  120 kB firmware buffer
+; 0x3E0000 - 0x3FFFFF    8 kB unused
+
+
+; Write: WREG -> FLASH with address increment and wrap-around at 0x200000
+	extern	write_byte_ext_flash_plus_prof		; with    increase of ext_flash_dive_counter
+	extern	write_byte_ext_flash_plus_nocnt		; without increase of ext_flash_dive_counter
+	extern	write_byte_ext_flash_plus_nodel		; without increase of ext_flash_dive_counter, without delete on entering new page
+
 
-; Writes
-	extern	write_byte_ext_flash_plus			; write from WREG and increase address after write with banking at 0x200000
-	extern	write_byte_ext_flash_plus_nocnt		; no increase of ext_flash_dive_counter:3
-	extern	write_byte_ext_flash_plus_nodel		; does NOT delete 4kB Page when required
-	extern	write_byte_ext_flash_plus_header	; write from WREG and increase address after write
-	extern	ext_flash_byte_write				; writes one byte from WREG @ext_flash_address:3
-	extern	ext_flash_byte_write_comms			; without wait, ~86us fixed delay due to 115200 Bauds (Use with caution)
-	extern	write_spi1							; just (dummy)write to read a byte
+; Write: WREG -> FLASH with address increment and wrap-around at 0x400000
+	extern	write_byte_ext_flash_plus_comms		; without wait for use with fast comm (~86us fixed delay due to 115200 Bauds - use with caution)
+
+
+; Read: block-read FLASH -> WREG
+	extern	ext_flash_read_block_start			; initial    read of one  byte at ext_flash_address:3
+	extern	ext_flash_read_block_0x40			; subsequent read of next byte(s) with wrap-around at 0x400000
+	extern	ext_flash_read_block_0x20			; subsequent read of next byte(s) with wrap-around at 0x200000
+	extern	ext_flash_read_block_stop			; terminate  read
 
-; Delete
-	extern	ext_flash_erase_logbook				; erases logbook memory (000000h -> 2FFFFFh -> 3MByte)
-	extern	ext_flash_erase4kB					; erases 4kB sector @ext_flash_address:3
+
+; Erase:
+	extern	ext_flash_erase_4kB					; erase one 4 kB sector @ext_flash_address:3
+	extern	erase_complete_logbook				; erase complete logbook (FLASH and EEPROM)
 
-; Reads
-	extern	ext_flash_read_block_start			; block read start and reads one byte@ext_flash_address:3 into WREG
-	extern	ext_flash_read_block				; read another byte into WREG
-	extern	ext_flash_read_block_stop			; stop block read
-	extern	ext_flash_byte_read					; read one byte@ext_flash_address:3 into WREG and ext_flash_rw 
-	extern	ext_flash_byte_read_plus			; return data read in WREG and ext_flash_rw and increase address after read with banking at 0x200000
-	extern	ext_flash_byte_read_plus_0x20		; return data read in WREG and ext_flash_rw
+
+; Protection:
+	extern	ext_flash_enable_protection			; enable  write protection
+	extern	ext_flash_disable_protection		; disable write protection
+
 
 
 ;-----------------------------------------------------------------------------
 ; Macros
+;-----------------------------------------------------------------------------
 
-; decrease ext_flash_address:2 by the 8 bit value "ext_flash_temp1"
-	extern	decf_ext_flash_address0
-decf_ext_flash_address	macro	ext_flash_temp1
-		movlw	ext_flash_temp1
-		call	decf_ext_flash_address0
+
+; read 1 byte from FLASH to WREG with address auto-increment and wrap-around at 0x200000
+;
+; the byte read is also copied to ext_flash_rw
+;
+FLASH_CW_READ_0x20	macro
+	extern	ext_flash_byte_read_plus_0x20
+	call	ext_flash_byte_read_plus_0x20
+	endm
+
+
+; read 1 byte from FLASH to memory with address auto-increment and wrap-around at 0x200000
+;
+; mem_address: address:2 containing target address in memory
+;
+FLASH_CC_READ_0x20	macro	mem_address
+	extern	ext_flash_byte_read_plus_0x20
+	call	ext_flash_byte_read_plus_0x20		; read from flash
+	movff	WREG,mem_address					; copy to   memory
+	endm
+
+
+; read 2 bytes from FLASH to memory with address auto-increment and wrap-around at 0x200000
+;
+; mem_address: address:2 containing start address in memory
+;
+FLASH_II_READ_0x20	macro	mem_address
+	extern	ext_flash_byte_read_plus_0x20
+	call	ext_flash_byte_read_plus_0x20		; read 1st byte from flash
+	movff	WREG,mem_address+0					; copy 1st byte to   memory
+	call	ext_flash_byte_read_plus_0x20		; read 2nd byte from flash
+	movff	WREG,mem_address+1					; copy 2nd byte to   memory
 	endm
 
-; increase ext_flash_address:2 by the 8 bit value "ext_flash_temp1"
-	extern	incf_ext_flash_address0
-incf_ext_flash_address	macro	ext_flash_temp1
-		movlw	ext_flash_temp1
-		call	incf_ext_flash_address0
+
+; read a range of data from FLASH to memory (destroys WREG, FSR1) - wraps around at 0x400000
+;                                                                 - increments ext_flash_address
+; flash_start : address:3 containing start address in flash
+; memory_start: address:2 containing start address in memory
+; range       : literal:1 giving the number of bytes to read (1-256)
+;
+FLASH_RR_READ		macro	flash_start, memory_start, range
+	MOVTT	flash_start,ext_flash_address			; set start address in FLASH
+	lfsr	FSR1,memory_start						; set start address in memory
+	movlw	low(range)								; set size of range to read
+	extern	ext_flash_read_range
+	call	ext_flash_read_range					; execute range-read
+	endm
+
+
+; write a range of data from memory to FLASH (destroys WREG, FSR1) - Attention: range must fit into a 256 byte block!
+;                                                                  - does not increment ext_flash_address!
+; memory_start: address:2 containing start address in memory
+; flash_start : address:3 containing start address in flash
+; range       : literal:1 giving the number of bytes to write (1-256)
+;
+FLASH_RR_WRITE		macro	memory_start, flash_start, range
+	lfsr	FSR1,memory_start						; set start address in memory
+	MOVTT	flash_start,ext_flash_address			; set start address in FLASH
+	movlw	low(range)								; set size of range to read
+	extern	ext_flash_write_range
+	call	ext_flash_write_range					; execute range-write
 	endm
 
-; increase ext_flash_address:2 by the 8 bit value "ext_flash_temp1" with banking at 0x200000
-	extern	incf_ext_flash_address0_0x20
-incf_ext_flash_address_0x20	macro	ext_flash_temp1
-		movlw	ext_flash_temp1
+
+; move forward in FLASH with wrap-around at 0x400000 to 0x000000
+;
+; increment: literal (1-255)
+;
+ext_flash_inc_address_0x40		macro	increment
+		movlw	increment
+		extern	incf_ext_flash_address0_0x40
+		call	incf_ext_flash_address0_0x40
+	endm
+
+
+; move forward in FLASH with wrap-around at 0x200000 to 0x000000
+;
+; increment: literal (1-255)
+;
+ext_flash_inc_address_0x20		macro	increment
+		movlw	increment
+		extern	incf_ext_flash_address0_0x20
 		call	incf_ext_flash_address0_0x20
 	endm
+
+
+; decrement length count
+;
+; decrement: literal (1-255)
+;
+ext_flash_dec_length			macro	decrement
+		movlw	decrement
+		extern	decf_ext_flash_length0
+		call	decf_ext_flash_length0
+	endm