KEYENCE N-410 - Manual (Page 100)

6-4
S
er
ia
l Com
m
u
n
icat
ion
6
6-2 Details of Data Communication
• The PASS and RTRY formats
PASS , PASS ,
are all possible. At the head of the command, or at the end may be added.
• All commands can be received while waiting for a PASS signal. In this case, a response
(such as OK) to a command can be sent without delay.
• If an SSET command is sent to the N-410 while it is waiting for a PASS signal, the send buffer
will be cleared and setting mode will be initiated.
"Changing to setting mode" (Page 4-20)
 ACK/NAK protocol
This is similar to the PASS/RTRY protocol explained above except that, instead of PASS
(06H) is sent and instead of RTRY, (15h) is sent. Besides the differences in the
character strings used, all operations are identical.
 RTS/CTS protocol
• Turning off the RS-232C RTS signal allows the device to wait to send data. When RTS is turned on,
the data is sent.
• Reading can still occur while RTS is turned off. If this happens, the read data will be stored in the
N-410 send buffer.
Data in the send buffer will be cleared if there is a buffer overflow. In this case, the N-410 will halt,
RTS will be turned on and the N-410 will send an OVER signal to the host computer. The N-410 will
reactivate upon receiving an OVCLR signal or having the TEST switch pressed.
Refer to
"Send Buffer Capacity" (Page 4-9) for more information on send buffer capacity and
the OVER signal.
RTS/CTS can be used with other protocols.
CR STX ETX
ESC LF
Note
ACK
NAK
Note