YOKOGAWA WT110 User Manual page 119

Explanation
(Control method when sending data to computer)
Software
handshake
Sending stops
when X-off is
received, and
sending is
resumed when
X-on is
received.
0
Ο
1
Ο
2
Ο
3
4
5
6
7
Used
IM 253401-01E
12.3 Setting the Mode, Handshaking Method, Data Format and Baud Rate
Mode Setting
Refer to page 12-1 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
Hardware 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
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 16 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.
64 bytes
Used
Free, 48 bytes
Used
Data receiving control
(Control method when receiving data from computer)
Software
Hardware handshake
handshake
X-off is sent CD(DTR) is
No
when received set to False
handshake
data buffer when
becomes 3/4- received data
full, and X-on buffer
is sent when becomes 3/4-
received data full, and is set
buffer to True when
becomes 1/4- received data
full. buffer
becomes 1/4-
full.
Ο
Ο
When handshaking is in use,reception
of data will stop when the free space in
the buffer drops to 16 bytes since data
cannot be passed to the main program
Free, 16 bytes
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 48 bytes.
Whether handshaking is in use or not,
if the buffer becomes full, any
additional data received is no longer
stored and is lost.
CA(RTS) is
No
set to False
handshake
when
received data
buffer
becomes 3/4-
full, and is set
to True when
received data
buffer
becomes 1/4-
full.
Ο
Ο
Ο
Ο
Ο
Ο
Ο
12-5
12