15.3 Handshaking
When using the serial (RS-232) interface for transferring data, it is necessary to
synchronize the equipment so that data is not transmitted in excess of the receive buffer
on the receiving end (overrun). This procedure is called handshaking. The GS820 can
use any of the three methods below. Match the setting with your PC.
No Handshaking
If the entire command sequence fits in the receive buffer (64 K on the GS820) or if a
query command is included in the middle of the command sequence, overrun will not
occur.
Select no handshaking if you are transmitting data in this manner.
Hardware Handshaking (CTS/RTS)
Hardware handshaking stops the transmission by setting CTS to false before the receive
buffer becomes full and resumes the transmission by setting CTS to true when there is
enough free space in the receive buffer.
Software Handshaking (XON-XOFF)
Software handshaking stops the transmission by sending an XOFF code (0X13) before
the receive buffer becomes full and resumes transmission by sending an XON code (0X11)
when there is enough free space in the receive buffer.
Software handshaking can be used by wiring only the data line, but binary data that
includes XON (0X11) or XOFF (0X13) cannot be transmitted.
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IM 765601-01E