Setting Of Transmission Specifications. Main Channels - Mitsubishi Electric AJ71C24-S6 User Manual

4.
SElTlNGS AND PROCEDURES BEFORE OPERATION
MELSEC-A
'OINT
Key points when setting modes
(1)
The RS-232C and RS-422 transmission specification protocols are iden-
tical. (See Section 4.3.2).
(2) To use the RS-232C and the RS-422 with a single mode, set the mode
switch to "1" to "8".
(3) If there is any interface which is not connected to any external device
when the mode setting is at
" 9
to
"DM,
noise will come in through such
an interface and normal communications cannot be done. In such a
case, change the mode setting to "1" to
"8".
(4) When the comwters and the AJ71C24 modules are connected in an
m:n
multidrop link'with the dedicated protocol, do not use protocol 3 ("7",
"C")
(5) Sections 2.3.1 to 2.3.6 and 4.5.4 give the examples of settings with
different system configurations.
4.3.2
Setting of transmission specifications, main channels, and terminal resistance
-
Position
of
Setting
Switch
Setting
of
Setting
Setting Notes
S w ~ t c h e s Switches
ON OFF
Main channel
Valid for
RS-232C modes
"enabled" is
I
SW18
I
S t o ~ bit
I
2 bits
I
1 bit
1
.
I
SW21
1
Sum check
/
Enabled
1
Disabled
I
-
SW22
SW23
sW24
Write
during RUN
Send area
terminal
resistance
4 - 6
Receive
;kr%nal
resistance
Enabled
Present
Present
Disabled
Absent
Absent
-
Valid only
when RS-422
is used