Introduction
I. Configuring SCU map
1. In Cx-Programmer, set port 2 mode User, Gateway, 9600, 8, N, 1:
2. Transfer the settings in the map.
Warning: the value of Serial Gateway Response timout should always be less than the timeout defined in the CMND (C 5) multiplied by the number of tests
II. Programming instruction CMND
| @CMND490 | |
| Source | Modbus Query preceded FINS command code 2804 (Modbus conversion) |
| Destination | Mailing address for reply |
| Control | Execution parameters of the instruction |
The destination instructions CMND, SEND, RECV are intelligently made using the traditional routing PURPOSES, No network N + No node n + u. No Unit
Since the V3 version of CPU CJ / CS, the recipient unit may be appointed directly from the Unit No. added as an offset. This trick of writing allows you to dispense with a routing table in the PLC.
| Without routing table | Network | Node | Unit |
| SCB (card inserted in the UC) | 0 | 0 | Port 1 : E4 Port 2 : E5 |
| SCU (maps) | 0 | 0 | Port 1 : 80 + 4x n° Unit Port 2 : 81 + 4x n° Unit |
1. Writing Query (0x10) from ABCD in 0002 via the register map SCU21 port 1 Unit No. 0
| Description of the Source block | Example | ||
| S | 2804 -> FINS Code for Modbus conversion | 2804 | |
| S+1 | No. of slave | Function code | 0110 |
| S+2 | Modbus write register address | 0002 | |
| S+3 | Amount of write register | 0001 | |
| S+4 | Qty bytes (S 3) x2 | data (MSB) | 02AB |
| S+5 | data (low) | not used | CD00 |
| Description of the Destination block | Example | ||
| D | 2804 -> FINS Code for Modbus conversion | 2804 | |
| D+1 | Code to execute the FINS command | 0000 | |
| D+2 | No. of slave | Function Code | 0110 |
| D+3 | Modbus register address | 0002 | |
| D+4 | Amount of Modbus register | 0001 | |
| Description of the Control block | Example | |||
| C | Size of the query S (11 bytes) | 000B | ||
| C+1 | Size of the expected response D (10 bytes) | 000A | ||
| C+2 | Recipient network. The FINS command | 0000 | ||
| C+3 | Destination node | Unit destination | 0080 | |
| C+4 | Response | Logical port | Number of tests | 0000 |
| C+5 | Response time 2s 1 = 0000 to FFFF (0.1 to 6553.5 s) | 0000 | ||
2. Reading Query (0x03) of words to address 01FF via map SCU21 port 2 Unit No. 2
| Description of Source block | Example | ||
| S | 2804 -> FINS Code for Modbus conversion | 2804 | |
| S+1 | No. of slave | Function Code | 0103 |
| S+2 | Modbus read register address | 01FF | |
| S+3 | Amount of read register | 0002 | |
| Description of Destination block | Example | |||
| D | 2804 -> FINS Code command | 2804 | ||
| D+1 | Code to execute the FINS command | 0000 | ||
| D+2 | No. of slave | Function code | 0103 | |
| D+3 | Quantity of bytes | Data (MSB) | 0400 | |
| D+4 | 1st read data (low) | 2nd read data (MSB) | 0100 | |
| D+5 | 2nd read data (low) | Not used | 0200 | |
| Description of Control block | Example | |||
| C | Size of the query S (8 bytes) | 0008 | ||
| C+1 | Size of the expected response D (11 bytes) | 000B | ||
| C+2 | Recipient network. The FINS command | 0000 | ||
| C+3 | Destination node | Unit destination | 0089 | |
| C+4 | Response | Logical port | Number of test | 0000 |
| C+5 | Response time 2s 1 = 0000 to FFFF (0.1 to 6553.5 s) | 0000 | ||
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