Led Signals And Displays - Mitsubishi Electric AJ71C24-S6 User Manual

4. SElTlNGS AND PROCEDURES BEFORE OPERATION
MELSEC-A
4.2.2
LED signals and displays
~
-
LED Area Details
9
.ED
NO.
-
16
17
18
19
20
21
22
23
25
Meaning
lED
1
LED
I
of LED
NO.
Display
qTJGr-
RS-232C transmining
2
1
2-RD
1
RS-232C receiving
2-NEU RS-232C neutral
4~
I
I I
5 2-ACK RS-232C ACK
2-NAK RS-232C NAK
+
4-NEU RS-422 neutral
1 1
I .
I I
10
4-SD
RS-422 transmission
Status
11 4-RD
RS-422 received data
status
,6 2-ClN
Result of RS-232C and
PC CPU communications
US-232C paritylsum
l7
1
2-P1S
I
check errpr
I I
19
2.510 RS-232C SIO error
CPU cornmunncations
RS-422 paritylsum cneck
22
1
4-PRO
I
US-47.2 protocol error
4 - 3 0 RS-422 SIO error
I
25
CPUR/W Communications with
PC CPU
Normal
I
Error
I
ON
Flashes during data
transmission
OFF
Flashes during data
receive
sion se-
After send- After send-
OFF
ing NAK ing ACK
Transmis-
sion se-
quence EN0
*
initial state received
(waiting for
FNOI
After send- After send-
OFF
ing ACK ing NAK
After send- After send-
OFF
ing NAK ing ACK
Flashes during data
transmission
OFF
Flashes during data
receive
OFF
See (4)
below
Normal
Dverrun,
iraming error Norma'
Paritylsum See(4)
:heck error below
laritylsum
:heck error Normal
;ommunica-
:ion
X O ~ O C O I
3rror
3verrun,
'raming error
-lashes during ccm-
ndnications with PC CP- ON
O N at no commcnica-
varies according to the switch setting as shown in the following table.