Delta DVP-ES2 User Manual

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D V P - E S 2 / E X 2 / S S 2 / S A2 / S X 2 / S E O p e r a t i o n M a n u a l - P r o g r a m m i n g

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receive PDOs are called PDO consumers.

The PDO is described by means of the “producer/consumer mode”. The data is transmitted
from one producer to one or many consumers. The data which can be transmitted are
limited to 1-byte data to 8-byte data. After the data is transmitted by the producer, the
consumer does not need to reply to the data. Every node in the network will detect the data
information transmitted by the transmission node, and decides whether to process the data
which is received.

Every PDO is described by two objects in the object dictionary: The PDO communication
parameters and the PDO mapping parameters
The PDO communication parameters: The COB-ID which will be used by PDO, the

transmission type, the prohibition time, and the cycle
of the counter

The PDO mapping parameters: They include the object list in an object dictionary. These

objects are mapped into the PDO, including the data length
(in bits). To explain the contents of the PDO, the producer
and the consumer have to understand the mapping.

The PDO transmission mode: synchronous and asynchronous
Synchronous: Synchronous periodic and synchronous non-periodic
Asynchronous: The PDO is transmitted when the data changes, or it is transmitted after a

trigger.

The transmission modes supported by are as follows.

Type

PDO transmission

Periodic

Non-periodic

Synchronous Asynchronous

RTR

0 X

1 – 240

254 X
255 X

Mode 0: The PDO information is transmitted only when the PDO data changes and the

synchronous signal comes.

Modes 1~240: One piece of PDO information is transmitted every 1~240 synchronous

signals.

Mode 254: The trigger is defined the manufacturer. The definition of the PLC is the same as

mode 255.

Mode 255: PDO is transmitted when the data changes, or it is transmitted after a trigger.
All the data in the PDO has to be mapped from the object dictionary. The following is an
example of the PDO mapping.

PDO_1

Application object C

zzh

zzzzh

Application object B

yyh

yyyyh

Application object A

xxh

xxxxh

Object dictionary