Sartorius MA150 Operating Instructions Manual page 43

Synchronization
During data communication between
moisture analyzer and computer,
messages consisting of ASCII characters
are transmitted via the interface.
For error-free data communication,
parameters for baud rate, parity,
handshake mode and character format
must be identical for both units.
You can adapt your moisture analyzer
by setting corresponding parameters in
the Setup menu.
If you do not connect a peripheral
device to the analyzer's interface port,
this will not generate an error message.
Handshake:
The Sartorius balance interface (SBI)
on the moisture analyzer has transmit
and receive buffers. You can define
the handshake mode in the Setup
menu:
– Hardware handshake (CTS/DTR)
– Software handshake (XON, XOFF)
Hardware handshake:
When using hardware handshake,
1 further character can be transmitted
after CTS ("clear to send").
Software handshake:
Software handshake is controlled
with XON and XOFF. When a device is
switched on, XON must be transmitted
to enable any connected device to
communicate.
When software handshake is configured
in the Setup menu, hardware handshake
becomes active after the software hand-
shake.
The data transmission sequence is as
follows:
Moisture –– byte ––> Computer
analyzer –– byte ––> (receiving
(transmitting –– byte ––>
device) –– byte ––>
<–– XOFF ––
–– byte ––>
–– byte ––>
...
(pause)
...
<–– XON ––
–– byte ––>
–– byte ––>
–– byte ––>
–– byte ––>
Transmitting device:
Once XOFF has been received, it prevents
further transmission of characters.
When XON is received, it re-enables the
transmitting device to send data.
Receiving device:
To prevent too many control commands
from being received at one time, XON is
not transmitted until the buffer is almost
empty.
Activating data output:
Data can be output after a print
command or automatically and
synchronously with the analyzer
display.
Data output after print command:
The print command can be sent
by pressing r or with a software
command (Esc P).
device)
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