Int 7F Fn 08  - G8bpq V4.00+ - Host Mode - Port Control/information        [N]

   AH = 08h
   AL = stream number (01h-40h)

Return: ES:DI -> 10-byte buffer containing blank-padded callsign
   ---v4.05+ ---
   AL = radio port to which channel is connected (level 2)
   AH = session type (see below)
   BX = L2 paclen for session
   CX = maximum frame size
   DX = L4 window size or 0000h if not L4 circuit
Program: the G8BPQ AX25 Networking Package is amateur packet radio software by
     John Wiseman which allows a PC to act as a node in an AX.25 network

See Also: AH=01h"G8BPQ",AH=02h"G8BPQ",AH=03h"G8BPQ",AH=0Ah"G8BPQ"

Bitfields for session type:
 bit 0 L2LINK
 bit 1 SESSION
 bit 2 UPLINK
 bit 3 DOWNLIND
 bit 5 BPQHOST