Tamagotchi Friends packet format:
=================================

[F0] sync byte
[TT] packet type
[LL] data length
.... packet data
[CS] checksum: sum of all bytes except sync byte and checksum byte

Packet types:
=============
00 connect packet             (sender initiates)
01 connect acknowledge packet (reciever acknowledges)

04 BFF VISIT packet			  	(sender)
05 BFF VISIT acknowledge packet (reciever)

06 BFF BUMP packet      (sender)
07 BFF BUMP acknowledge (gives item?/reciever aknowledges item?)

10 MAIL packet             (sender)
11 MAIL acknowledge packet (reciever)

charset:
========
 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U 
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 

 V  W  X  Y  Z SPACE  .  '  -  !  ?  0  1  2  3  4  5  6  7  8  9
15 16 17 18 19    1A 1B 1C 1D 1E 1F 20 21 22 23 24 25 26 27 28 29

tamagotchis:
------------
01 = Aukumotchi    (boy)
04 = Turtletchi	   (boy)
05 = Terupotchi	   (girl)
06 = Petithanatchi (girl)
09 = Bokuhoshi	   (boy)

items:
------
FD - Jackpot item?

=======================================
DIAGNOSTIC MODE
=======================================
-- diagnostic mode send packet --
F0 - sync
00 - connect packet
0F - length
01 \ packet number
00 | packet type
01 | 
02 /
00 \
00 | Tamagotchi 
00 /
00 \ name
00 |
00 |
00 |
00 |
00 |
00 |
00 /
13 - csum

=======================================
BFF bump 1
=======================================
----  BFF sender ----
F0 - sync
00 \ connect packet
0F / length
01 \ Packet number?
00 | same as this packet type
07 | tamagotchi unique ID?
2D / tamagotchi unique ID?
00 \ ?
09 | tamagotchi Bokuhoshi
00 / ?
01 \ B name
0B | L
08 | I
0D | N
0A | K
18 | Y
1A | space
1A / space
C4 - csum

----  BFF reciever ----
F0 sync
01 Packet type BFF reciever?
0F length
01 \
01 same as this packet type
0F 
0B /
00 \
06 tamagotchi Petithanatchi
80 /girl?
02 \
08  name
01
08
1A
1A
1A
1A /
2D csum

----  BFF sender ----
F0 sync
06 type
04 length
01 \	tamagotchi generation?
06      (same as this packet byte 1)
07		(same as byte 5 BFF packet)
2D /	(same as byte 6 BFF packet)
45 csum

----  BFF reciever ----
F0 sync
07 type
05 length
01 \	tamagotchi generation?
07 		(same as this packet byte 1)
0F		(same as byte 5 BFF packet)
0B /    (same as byte 6 BFF packet)
06 	    (same as byte 8 BFF packet) gifted item?
34 csum

=======================================
send mail
=======================================

----  MAIL sender ----
F0
00 connect packet
0F
01 \
00 same as this packet type
07
2D /
00 \
09
00 /
01 \ name
0B   
08
0D
0A
18
1A
1A /
C4
----  MAIL reciever ----
F0 sync
01 handshake
0F length
01 \
01 same as this packet type
0F 
0B /
00 \
06  
80 /
02 \ name
08  
01
08
1A
1A
1A
1A /
2D
----  MAIL sender ----
F0 sync
10 mail packet
1C length
01 \
10
07
2D /
00 \A   mail text
01  B
02  C
1B  .
1C  '
1D  -
1E  !
1F  ?
20  0
29  9
1A  SPACE
1A  SPACE
1A  SPACE
1A  SPACE
1A  SPACE
1A  SPACE
1A  SPACE
1A  SPACE
1A  SPACE
1A  SPACE
1A  SPACE
1A  SPACE
1A  SPACE
1A /SPACE
BA
----  MAIL reciever ----
F0 sync
11 acknoledge mail
04 length
01 \
11 same as this packet type
0F
0B /
41 csum

=======================================
BFF bump 2 (new reciever CHIBI)
=======================================
----  BFF sender ----
F0
00
0F
01 \
00
07
2D /
00 \
09 - tamagotchi
00 /
01 \ name BLINKY
0B 
08
0D
0A
18
1A
1A /
C4
----  BFF reciever ----(pinkbotchi)
F0 - sync
01 - BFF ack
0F - length
01 \
01
2E
25 /
00 \
02 - tamagotchi pinkbotchi?
80 /
02 \ name CHIBI
07  
08
01
08
1A
1A
1A /
4F
----  BFF sender ----
F0 - sync
06 - BFF send
04 - length
01 \
06 
07
2D /
45
----  BFF reciever ----
F0 - sync
07 - BFF ack
05 - length
01 \
07
2E
25 /
FD - Jackpot item?
64
=======================================
BFF VISIT (CHIBI visits BLINKY)
=======================================

----  BFF VISIT sender ----
F0 - sync
00 - connect packet
0F - length
01 \
00 - connect packet
2E
25 /
00 \
02 - tamagotchi
80 /
02 \ name CHIBI
07
08
01
08
1A
1A
1A /
4D - csum

----  BFF HOST reciever ----
F0
01 - connect ack packet
0F
01 \
01 - ack packet
07
2D /
00 \
09 - tamagotchi 
00 /
01 \ name BLINKY
0B
08
0D
0A
18
1A
1A /
C6
----  BFF VISIT sender ----
F0 - sync
04 - visit packet
05 - length
01 \ 
04   packet type
2E
25 /
01 - ?
62
----  BFF HOST reciever ----
F0 - sync
05 - visit ack packet
07 - length
01 \
05 - visit ack packet 
07
2D /
02 \ Tamagotchi ?
22   ?
3E / ?
A8
=======================================
GIVE ITEM (MEAL)
=======================================
---- GIVE sender ----
F0-
00-
0F-
01\
00|
07|
2D/
00\
09|
00/
01\
0B|
08|
0D|
0A|
18|
1A|
1A/
C4-
---- RECIEVE reciever ----
F0-
00-
0F-
00\
01
2E
25/
00\
05  Tamaagotchi Petithanatchi
80/ Girl?
02
07
08
01
04
1A
1A
1A
52
---- GIVE sender ----
F0-
02- give item packet
06- length
01\
02|
07|
2D/
00\ ?
04/ SALAD
43-
---- RECIEVE reciever ----
F0-
03-
04-
01\
03|
17|
25/
5E