FBB Unproto message lists

 FBB software allows sending unproto lists of message. This is validated
separately on each port (letter L in PORT.SYS). Unproto address is FBB with
the following header :

fm F6FBB-1 to FBB ctl UI

 An unproto list line is sent on every validated port each time a message is
recorded. The line is in the form :

12345 B 2053 TEST@ALL F6FBB 920325 This is the subject

 If a message number is missing or does not exist the line will be :

12346 #

 This allows a system listening to the UI packets on a frequency to create a
list identical to the one of the BBS, and then the user will not have to
connect the BBS to know the list of messages and bulletins.

 A control can be done on the number of the messages to check if a line is

 If the remote system receives a new line, and a line is missing, it only has
to send an unproto frame addressed to the BBS callsign like this :

fm FC1EBN-3 to F6FBB-1 ctl UI
? 00002EE00E

 This will be taken in account only if the user has the U flag validated (EU

 If the user has not his flag validated in the BBS, he will receive a line
like :

fm F6FBB-1 to FBB ctl UI
12200 / callsign

 In this case, the the remote software MUST stop asking unprotoes.

 The first 8 digits are the hexadecimal number of the requested start of the
list (here 00002EE0 -> 12000) and the last two digits are the sum of the four
bytes anded with FF (0E).

 The BBS will then starts sending lines from the requested number up to the
last message number.

 If the number requested seems to be too far from the current line, the BBS
can readjust the request of "callsign" while sending :

fm F6FBB-1 to FBB ctl UI
12200 ! CALLSIGN
12201 B 2040    TEST@FRA    F6FBB  920325 This is a bulletin
12202 #
12203 P 206    F6ABJ@F6ABJ  F6FBB  920325 Hello Remy.

and then starts sending lines from 12201. The remote system must change its
base number to 12201.

  If the number requested is greater than the last message received in the
BBS, the BBS will send a line like :

 12300 !!

 This indicates that the list in the remote system is up to date. The last
received message in the BBS is 12300.

 The remote system can also connect the BBS and ask for messages in binary
compressed mode using the following sequence :

     BBS                                    Remote system
                                            Connection request

Welcome in Toulouse, Gerard.
                                            F< #Msg
Binary compressed message #Msg
is sent using format described
in appendix 7

 From TPK version 1.80 (packet communication program developed by FC1EBN),
this protocol is implemented.