Omron V720S Series, Руководство по эксплуатации

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Wiring Method Section 4-4
4-13
■
Example of wiring between host and Reader/Writer
Host side Reader/Writer side
Connector plug
(accessory)
Con-
nected
to
Name
Pin num-
ber
RD １
SD
２
SG ３
+ +
４
- -
５
■
Example of cabling between Reader/Writers
Reader/Writer side (COM1) Reader/Writer side (COM2)
Connector plug (accessory) Connector plug (accessory)
Name Pin number Name Pin number
1 RD RD 1
2 SD SD 2
3 SG SG 3
4 + + 4
5 - - 5
Note
•
Leave the pin for RS-232 unconnected.
•
Be sure to use a twisted-pair wire for the signal line.
•
Be sure to use a wire with a thickness of AWG20 for the signal line.
•
When you use a shielded cable, be sure to ground on the host side.
•
Make sure that the total cable length for 1-to-1 and 1-to-N connection is
not longer than 300 m.
Note When you connect more than one Reader/Writer, give special attention to
communications timing between Reader/Writers. To ensure proper timing,
you will need to perform both theoretical calculation of timing and verification
of communications on real machines.
1) The Reader/Writers cannot operate simultaneously except through
polling-related commands. This means that, even when you connect more
than one Reader/Writer, only one Reader/Writer can communicate with the
host at a time.
Multiple Reader/Writers can access the host only in a time-phased manner.
2) When you use an Auto command, the Reader/Writer will not return a
response but continue to wait if there are no Tags in the communications area.
In this state, if you send a command to another Reader/Writer, no command
will be accepted until a response is returned. To avoid this, you must abort
the Auto command using the STOP command before sending any command.
3) Polling-related commands do not support any commands but Auto
commands. These commands are not available in Multiple Access Mode
(which permits access to multiple Tags) to avoid processing complexities.
2
3
4
Pin layout when cable connector on
Reader/Writer is viewed from engagingface
Port
Terminal No.
Polarity.
COM1 COM2
4 5
+
-
4 5
+
-
1
5
* Short circuits have been established within RS-485
between Pin 4 of COM1 and Pin 4 of COM 2 and between
Pin 5 of COM2 and Pin 5 of COM1.