Chapter 8 - Service Data Objects - Honeywell DPS CANopen User's & Technical Manual

Digital Pressure Sensor with CANopen
The units can be stored in EEPROM by using the store com-
mand, i.e. object 0x1010. Also the default unit of PSI can be
restored using the restore command i.e. object 0x1011. Table
20 provides a list of units that the Digital Pressure Sensor with
CANopen , Model DPS, supports.
®
Table 20. Units Supported by the Digital Pressure
Sensor with CANopen
®,
Unit Type Unit
Non-SI psi
SI Bar
SI KPa
7.3 PDO Mapping
The Digital Pressure Sensor with CANopen
lows two different objects to be mapped into the process data
object:
1. Pressure in signed integer format (default)
2. Raw pressure data
The mappable objects are shown in Table 21.
Table 21. Objects That Can Be Mapped to the PDO
Object (hex) Sub Index
(hex)
6130 1
7100 1
The default mapping of the Digital Pressure Sensor with CANo-
pen , Model DPS, is shown in Table 22.
®
Table 22. Digital Pressure Sensor with CANopen
Initial PDO Map
Object Sub Value (hex) Description
Number Index
(hex) (hex)
1A00 00 01
1A00 01 20013061
14 sensing.honeywell.com
Model DPS
Code
00 00 AB 00
00 00 4E 00
00 00 22 03
, Model DPS, al-
®
Description
Pressure reading REAL32
Pressure reading INT16
1 object mapped
1st object is process value
stored at 6130, sub index
1, length 32 bits. This can
be changed to filed value
7100, subindex 1, length
16 bits
, Model DPS
®

CHAPTER 8 - SERVICE DATA OBJECTS

The Service Data Object (SDO) is used to access the object
dictionary (OD) of a device. The requester of the OD access
is called the client and the CANopen
accessed and services the request, is called the server. The
client CAN-message as well as the reply server CAN-message
always contains 8 bytes (although not all bytes necessarily
contain meaningful data). A client request is always confirmed
by a reply from the server. The Digital Pressure Sensor with
CANopen , Model DPS, supports only one server SDO and no
®
client SDOs.
8.1 SDO Transfer
There are two mechanisms for SDO transfer:
• Expedited transfer: used for data objects up to 4 bytes in
length.
• Segmented transfer: for objects with length > 4 bytes.
The Digital Pressure Sensor with CANopen
lows only expedited SDO access (single CAN frame read/write
and response) to (and from) the object dictionary.
The Model DPS is capable of detecting errors within the SDO
protocol. If an error is detected then the Digital Pressure Sen-
sor with CANopen
message. Table 23 contains the supported abort codes and
their description.
Table 23. SDO
Abort Code Description
(hex)
® 0504
Client/server command specifier not valid or
001160504
unknown
0001
Attempt to read a write only object. Attempt
to read a write only object. Attempt to read a
write only object. Attempt to read a write only
0601 0001
object. Attempt to read a write only object to
read. Attempt to read a write only object. At-
tempt to read a write only object
0601 0002 Attempt to write a read only object
0602 0000 Object does not exist in object dictionary
0604 0041 Object cannot be mapped to the PDO
Sub-index does not exist. Attempt to read a
0609 0011 write-only object. Attempt to read a write-only
object
Value of parameter exceeded (only for write
access)Value of parameter exceeded (only for
0609 0031
write access) Value of parameter exceeded
(only for write access)
0800 0000 General error
50085804, Rev. B
device, whose OD is
®
, Model DPS, al-
®
, Model DPS, replies with an SDO abort
®