Overview
- Modular Controller Master can act as an Ethernet gateway
- Supports Red Lion devices using ASCII string protocol
- Can operate stand‑alone (no modules required) if Ethernet is enabled [rlcgateway_0 | Word]
Configuration Example (PAX Devices)
Device Setup
- PAXD → Address 1
- PAXI → Address 2
| Device | Register | Identifier |
|---|---|---|
| PAXD | Input Display | A |
| PAXD | Totalizer | B |
| PAXI | Count | A |
| PAXI | Setpoint 1 | M |
Serial Port Configuration
-
Driver:
Red Lion Instrument
Address Map Format
[Address][Register][Option], Example: 01A@, 01B@, 02A@, 01B!, 02M@,
Example Behavior
| String | Function |
|---|---|
| 01A@ | Read PAXD display |
| 01B@ | Read PAXD totalizer |
| 02A@ | Read PAXI count |
| 01B! | Reset PAXD totalizer |
| 02M@ | Write PAXI setpoint |
Option Characters
| Option | Character | Description |
|---|---|---|
| Abbreviated | @ | Short response |
| Reset | ! | Reset operation |
| Control | : | Control operation |
| Unsigned | # | Unsigned data |
| 32-bit | ^ | 32-bit support |
| Terminator | * | Transmission terminator |
Serial Blocks
Read Block
- Address:
R0 - Block size = number of read items
-
Direction:
PLC → System
Write Block
- New address range
- Block size = number of write items
-
Direction:
System → PLC
Ethernet Blocks
- Match block size with serial blocks
- Use same block lettering
- Direction is ignored [rlcgateway_0 | Word]
Modbus TCP/IP Mapping
| Modbus Register | Function |
|---|---|
| 40001 | PAXD Display |
| 40002 | PAXD Totalizer |
| 40003 | PAXI Count |
| 40004 | Reset Totalizer |
| 40005 | PAXI Setpoint |
Key Behavior
- Writing new value to reset register triggers reset
- Rewriting same value does not retrigger
- System distinguishes blocks by direction
- Writes read back over TCP/IP may return 65535 unless mirrored in read block [rlcgateway_0 | Word]
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