Watlow Series SD6 PID Controller with DeviceNet Addendum - Manual (Page 3)

Table 5. Descriptions of Elementary Data Types
Data Type Name Data Type Description
BOOL Logical Boolean with values TRUE and FALSE
BYTE Bit string — 8 bits
EPATH DeviceNet path segments
INT Signed 16-bit integer value
SHORT_STRING Character string (1 byte per character, 1 byte length indicator)
UDINT Unsigned 32-bit integer value
UINT Unsigned 16-bit integer value
USINT Unsigned 8-bit integer value
WORD Bit string — 16 bits
This appendix describes the DeviceNet protocol as it is
implemented in the Series SD6 controller. It primarily
describes the objects and attributes accessible via the
DeviceNet protocol. It may be necessary to refer to the
DeviceNet specification as a compliment to the information
found here.
DeviceNet Overview
The SD6 controller supports the object-based modeling
used in the DeviceNet concepts. This product is configured
as a Group 2 Only Slave device using the Predefined
Master/Slave Connection Set.
There are two main categories of objects, DeviceNet
Objects and Application Objects. DeviceNet objects handle
what is necessary for networking and communications.
Application Objects have access to the SD6 controller's
parameters and data.
Addressing
All data is referenced based upon a four-part definition:
Node (MAC ID) + Class + Instance + Attribute.
Table 4. Four Components to an Address, with
Ranges
Node Address (MAC ID) [0 to 63]
Class ID [1 to 255]
Instance ID [0 to 255]
Attribute ID [1 to 255]
Data Types
The descriptions of attributes in the following sections
includes the data type for each. Table 5 lists and describes
these data types.
DeviceNet Communications
Wa t l o w S e r i e s S D 6 P I D w i t h D e v i c e N e t ■ 3 ■