Async Link

Print version

Async Link protocol for MORSE

version 7.40


1. Introduction

The Async Link is the simplest protocol that creates an asynchronous
link between two points. The target address is determined by the protocol
parameter. Data is transferred to the radio channel without being modified
and no CRC is used.

2. Data Format

Data is created by a arbitrary combination of bytes of length 1 to
1550 bytes, (the optimum length of the packet for transmission through the
radio network is 100 to 500 bytes).

3. Implementation in Morse

Below is an example of processing data inserted to port SCC2, which
is set with the Async Link protocol:

Monitoring: source 690F5501|2.
10:58:29.039 rxsim   2 | S02
CNI mon     |toa      frm     |dst      src     |           size|TT N
10:58:29.040|                 |00005502 00005501|S02I   OUT    2||89 0user
RF mon      |toa      frm     |dst      src     |lNo!DQ!RSS size|TT N
10:58:29.040|690F5502 690F5501|690F5502 690F5501|002  RFTX     2 89 1dat
  • first monitoring contains inserted data AAAA

  • second monitoring contains unchanged data after transfer through
    the protocol. A destination address is added according to the

  • the third record represents a packet sent via the radio channel
    already furnished with all addresses

4. Configuration Parameters

The protocol uses a single parameter, which defines the address of
the opposite station.

ASYNC LINK parameters:
link destination

The parameter only contains the lower two bytes of the address.
Therefore it is necessary in the SIe menu to set address conversion with a
mask of max. length 16 bits. The rest of address is then added from the
node´s own address.

Note – the protocol contains the whole MORSE address in
the parameter.