Set switch 2ON if you don’t want parity checking, and
set it to OFF if you want parity checking.
If you have set switch 2to OFF, you must choose
whether you are going to use even or odd parity. IF
switch 5is ON, the SPC-8K will use odd parity, and if
this switch is OFF, the SPC-8K will use even parity. If
switch 2is ON, switch 5will have no effect.
Handshaking
“Handshaking” is the term used to describe the way in
which serial devices “say” to each other:
“Are you ready for me to give you more data?”
“No, I’m not –wait amoment.”(thinks and processes
data) “OK –I’m ready now. More data, please.”
Obviously, computer devices don’t use these words –
there are two ways in which they have these “conversa-
tions”. One way is by changing the voltage along one of
the serial lines (hardware or DTR handshaking). The
other way is by special codes which cannot be printed,
but are interpreted by computer devices along the lines
of the conversation above (software handshaking). An
older, less frequently-used method is called ETX/ACK,
and the other main method (more common than ETX/
ACK) is called XON/XOFF (sometimes called DC1/DC3).
Use switches 3and 4 to set the handshaking method
(usually called “protocol”):
Protocol Sw 3Sw 4
DTR(hardware) handshake ON ON
XON/XOFF ON OFF
ETX/ACK OFF ON
Connecting the SPC-8K converter
.Turn the printer and the computer OFF using their
power switches.
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