118158
‐
001
REV.
A
8
OF
20
1.4.2.
Messages
sent
from
eSL
unit
to
Host
The
message
sent
back
by
the
units
contains
the
received
command
and
one
or
more
data
strings.
If
no
data
is
to
be
sent
back,
a
$
character
is
sent
as
acknowledgment
that
message
was
received
without
errors.
If
the
unit
receives
a
message
in
error
it
will
send
an
error
code.
If
the
host
receives
a
message
in
error,
it
will
disregard
the
message
and
try
again.
The
following
are
the
messages
that
can
be
sent
from
unit
to
Host.
Unit
received
message
successfully.
It
sends
data
back
to
host
STXCMD,DATA,..,DATA,ETX
Unit
received
message
successfully.
No
data
to
be
sent.
It
sends
acknowledgement
STXCMD,$,ETX
Unit
received
message
in
error.
It
sends
error
code
STX,EC,ETX
Where:
STX
ASCII
0x02
Start
of
message
CMD
2
numeric
ASCII
characters
representing
the
command
ID.
See
commands
below.
,
ASCII
0x2C
character
DATA
One
or
more
data
strings
in
ASCII
format
and
separated
by
commas
ETX
ASCII
0x03
End
of
message
$
ASCII
character
indicating
message
was
received
successfully
EC
Error
code.
1:
Wrong
number
of
parameters
or
parameter
out
of
range
2:
Parsing
error
or
invalid
command
code.
