Read/write image data
Example:
A voltage signal is present at analog input 1. The required telegrams for reading the analog value are as follows:
Table 14: Example telegram for reading the value at the analog input
Byte | Meaning | Value (hex), sent by | ||||
|
|
|
| Master |
| Slave |
0 |
| Toggle byte | J page 44 |
|
| |
1 |
| Command: Read |
| 88 |
| – |
|
| Response: |
|
|
|
|
|
| Read successful |
| – |
| C2 |
2 |
| Len |
| 02 |
| 02 |
|
|
|
|
|
|
|
3 |
| Type | 8C |
| 8C | |
|
|
|
|
|
|
|
4 |
| Index |
| 021 |
| 021 |
5 |
| Data 1 |
| 00 |
| 4B |
6 |
| Data 2 |
| 00 |
| 03 |
7 |
| Data 3 |
| 00 |
| 00 |
8 |
| Data 4 |
| 00 |
| 00 |
|
|
|
|
|
|
|
1) 02 = Analog input I11
Byte 5 – Data 1 (Low Byte): 4Bhex
Byte 6 – Data 2 (High Byte): 03hex
J corresponding
The value 843 corresponds to the IO bit value of the analog converter. The following conversion is required for the actual analog value:
10 V | 10 V | ||
| × IO bit value => |
| × 843 = 8.24 V |
1023 | 1023 | ||
MN05013001E | For more information visit: www.EatonElectrical.com | 57 |
