YOKOGAWA WT210 User Manual page 183

11.3 Setting the Mode, Handshaking Method, Data Format and Baud Rate
Explanation
Sending stops
when X-off is
received, and
sending is
resumed when
X-on is
received.
0
1
2
3
4
5
6
7
11-6
Mode Setting
Refer to page 11-1 for more details.
Handshaking
To use an RS-232-C interface to transfer data between this instrument and a
computer, it is necessary to use certain procedures by mutual agreement to ensure
the proper transfer of data. These procedures are called "handshaking". Various
handshaking systems are available depending on the computer to be used; the same
handshaking system must be used for both computer and this instrument. This
instrument allows you to choose any handshaking method from the following eight
using the panel keys.
Handshaking method combinations (a circle indicates that the function is available)
Data sending control
(Control method when sending data to computer)
Software
Hardware handshake
handshake
Sending Sending
stops when stops when
CB (CTS) is CC (DSR)
False, and is False,and
sending is sending is
resumed resumed
when CB is when CC is
True. True.
Ο
Ο
Ο
Ο
Ο
Precautions Regarding Data Receiving Control
When handshaking is used to control received data, data may still be sent from the
computer even if the free space in the receive buffer drops below 64 bytes. In this
case, after the receive buffer becomes full, the excess data will be lost, whether
handshaking is in use or not. Data storage to the buffer will start again when there is
free space in the buffer.
Used
Used
(Control method when receiving data from computer)
handshake
X-off is sent
No
when received
handshake
data buffer
becomes 3/4-
full, and X-on
is sent when
received data
buffer
becomes 1/4-
full.
Ο
Ο
Ο
256 bytes
Free, 64 bytes
Free, 192 bytes
Used
Data receiving control
Software
Hardware handshake
CD(DTR) is CA(RTS) is
set to False set to False
when when
received data received data
buffer buffer
becomes 3/4- becomes 3/4-
full, and is set full, and is set
to True when to True when
received data received data
buffer buffer
becomes 1/4- becomes 1/4-
full. full.
Ο
Ο
Ο
Ο
When handshaking is in use,reception
of data will stop when the free space in
the buffer drops to 64 bytes since data
cannot be passed to the main program
fast enough to keep up with the
transmission.
After reception of data stops, data
continues to be passed to the internal
program. Reception of data starts
again when the free space in the buffer
inceases to 192 bytes.
Whether handshaking is in use or not,
if the buffer becomes full, any
additional data received is no longer
stored and is lost.
No
handshake
Ο
Ο
Ο
Ο
IM 760401-01E