Rockwell Automation 20-COMM-M Modbus/TCP Adapter - Manual (Page 46)

4-10 Using Modbus/TCP Function Codes
20-COMM-M Modbus/TCP Adapter User Manual
Publication 20COMM-UM014C-EN-P
Indirect Access Method
Adapter Parameters 38 - [Indirect Par #1] through 53 [Indirect Par #16]
allow reading and writing to contiguous or non-contiguous sets of
parameters for the drive or any of its connected peripherals using Function
Code 03, 16 or 23. This can be done by writing the Indirect Par #x Value
(formula shown below) to the corresponding Indirect Par #x parameter in
the adapter. Adapter Parameters 38 - [Indirect Par #1] through 53
[Indirect Par #16] enable you to set up a group of commonly read and
written parameters and transfer that data in one transaction.
Table 4.J shows
the Indirect Par #x target address ranges and the peripherals to which they
apply:
Table 4.J Indirect Par #x Target Address Ranges for Peripherals
To determine the value of an adapter Indirect Par #x for a specific device,
use the following formula:
Indirect Par #x Value = Device Starting Address + Parameter No.
For example, suppose the adapter is connected to the drive’s internal Port 5
and you want to use adapter Parameter 38 - [Indirect Par #1] to access
adapter Parameter 22 - [Reset Module] to reset the adapter. Using this
formula:
Indirect Par #x Value = 15000 + 22 = 15022
In this case, set adapter Parameter 38 - [Indirect Par #1] to a value of
“15022” to access adapter Parameter 22 - [Reset Module].
!
ATTENTION: Risk of equipment damage exists. When adapter
Parameters 38 - [Indirect Par #1] through 53 - [Indirect Par
#16] and their corresponding data registers are used to write
parameter data to Non-Volatile Storage (NVS) frequently, the
NVS will quickly exceed its life cycle and cause the drive to
malfunction. Do not create a program that frequently uses
Indirect Parameters to write parameter data to NVS. Datalinks do
not write to NVS and should be used for frequently changed
parameters. See
Using Datalinks on page 4-12 for more
information.
Address Range Peripheral
0…9999 Drive
10000…10999 Adapter
11000…11999 Peripheral connected to DPI Port 1
12000…12999 Peripheral connected to DPI Port 2
13000…13999 Peripheral connected to DPI Port 3
14000…14999 Peripheral connected to DPI Port 4
15000…15999 Peripheral connected to DPI Port 5
16000…16999 Reserved for future use
TIP: If the port to which the adapter is connected is not known, always use
“10000” for the Device Starting Address in the formula above. In this case,
set adapter Parameter 38 - [Indirect Par #1] to a value of “10022” for this
example to access adapter Parameter 22 - [Reset Module].