Rockwell Automation DeviceNet Communications Module - Manual (Page 94)

8-20 DeviceNet Communications Module
8.7 Multi-Drive Mode Explicit Messaging
Parameter addressing for Explicit messaging is different in
Multi-Drive mode than with Single-Drive mode. In Single-Drive
mode, the Instance value in the message equals the desired
parameter number in the drive. In Multi-Drive mode, an Instance
table is used to account for the parameters in the module and up to
5 drives. The parameters in the module and each of the drives are
offset by 400 hex (1024 decimal):
For example, to access parameter P39 (Accel Time 1) in each of the
drives, the following Instances would be used:
• Drive 0 Instance = 17447 (17408 + 39)
• Drive 1 Instance = 18471 (18432 + 39)
• Drive 2 Instance = 19495 (19456 + 39)
• Drive 3 Instance = 20519 (20480 + 39)
• Drive 4 Instance = 21543 (21504 + 39)
Figure 8.17 – Drive 4 Control Routine (Continued)
13
PerformParameterRead4
EN
DN
ER Type - CIP Generic
Message Control
ParameterRDMessage4 ...
MS G
14
PerformParameterWrite4
EN
DN
ER Type - CIP Generic
Message Control
ParameterWRMessage4 ...
MS G
15 Return
RET
(End)
Drive 4 parameters are accessed by adding 21504 decimal (5400 hex) to the
desired parameter number. For example, to access parameter 39 an Instance of
21543 (21504 + 39) is used.
Explicit Messaging Example
Instance Device Parameter
4000h (16384 dec) - 43FFh MDCOMM-DNET 0 - 1023
4400h (17408 dec) - 47FFh Drive 0 0 - 1023
4800h (18432 dec) - 4BFFh Drive 1 0 - 1023
4C00h (19456 dec) - 4FFFh Drive 2 0 - 1023
5000h (20480 dec) - 53FFh Drive 3 0 - 1023
5400h (21504 dec) - 57FFh Drive 4 0 - 1023