1.1
RS-232C Specifications
3
Chapter 1 S
pe
cificati
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XON/XOFF control:
•
When the data in the receive buffer exceeds 75% of
the buffer, XOFF(13H) is sent and the controller is
notified that there is not much space remaining in the
buffer.
•
Processing of the data in the buffer continues, and
then XON(11H) is sent and the controller is notified
that there is sufficient remaining space in the buffer
when the amount of data becomes less than 25%.
XON/XOFF control:
•
When XOFF is received, the sending of data is halted. When XON is received, the sending of data is
resumed.
Specifications
Chapter 1
1.1 RS-232C Specifications
Transmission Method
Communication method: Full duplex
Synchronous method: Start-stop synchronization
Transmission Speed
9600 bps, 19200 bps, 38400 bps, 57600 bps
Data Bits
8 bits
Parity
None
Stop bit
1 bits
Message terminator
(delimiter)
CR+LF, CR
Flow control
Software (XON/XOFF control)
"Handshake (About Buffer Flow Control)" (p.3)
Electrical
Specifications
Input voltage
level
Output voltage
level
5 to 15 V ........ ON
-15 to -5 V ....... OFF
5 to 9 V .......... ON
-9 to -5 V ........ OFF
Handshake (About Buffer Flow Control)
Control during Receiving
25%
85%
Input Buffer
Usage
Amount
Buffer Space
75%
Send XOFF
Send XON
Control during Sending
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