1. Overview
The Mitsubishi FX5U series PLC has a built-in positioning function that supports step control through table positioning commands. This article details the usage of the DRVTBL instruction, as well as the parameter settings and programming implementation for multi-table positioning.
2. Key Instruction Analysis
DRVTBL Instruction
The DRVTBL instruction is used to execute multiple positioning actions based on table data, supporting both step and continuous operation modes.
LD Format
plaintext
DRVTBL S1 S2 S3 S4 D
Parameter Description:
- S1: Axis Number (K1~K4)
- S2: Starting Table Row Number
- S3: Final Table Row Number
- S4: Operation Mode (K0: Step, K1: Continuous)
- D: End Flag Soft Element
ST Language Format
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ENO:=DRVTBL(EN, n1, n2, n3, d1, d2);
Parameter Description:
- EN: Execution Condition
- n1: Starting Table Row Number
- n2: Final Table Row Number
- n3: Operation Mode (K0: Step, K1: Continuous)
- d1: Axis Number
- d2: End Flag
3. Parameter Setting Steps
1. Positioning Parameter Configuration
In the GX Works3 software, navigate to:
<span>Parameters → FX5U CPU Parameters → Module Parameters → High-Speed I/O → Output Function → Positioning → Detailed Settings</span>
Set the pulse output mode to “PULSE/SIGN pulse + Direction” and configure the corresponding output terminals (Y0/Y4, etc.).
2. Positioning Table Settings
In the positioning data settings interface, click on “Axis 1 Positioning Data” to set control methods, positioning addresses, command speeds, and other parameters.
Control methods available:
- 20: Interpolated Operation (Relative Address Positioning)
- 22: Interpolated Operation (Absolute Address Positioning)
4. Step Operation Programming Example
1. LD Program
plaintext
DRVTBL K1 K1 K3 K0 M3
- K1: Axis 1
- K1: Starting Row 1
- K3: Ending Row 3
- K0: Step Mode
- M3: End Flag
2. Trigger Condition Settings
Trigger the SM5580 special relay through X3 to achieve step transfer:
plaintext
X3 SM5580<span>---| |-------(SET)</span>
3. Program Execution Flow
- X4 triggers the DRVTBL instruction to execute the first row of positioning data
- After the first row is completed, M3 is set ON
- Press X3, SM5580 is set ON, allowing execution of the second row
- Repeat until all positioning rows are completed
5. Application Case
Multi-Station Positioning Control
Set 3 positioning points to be executed sequentially in step mode:
| Row Number | Control Method | Positioning Address | Command Speed | Dwell Time |
|---|---|---|---|---|
| 1 | 20 | 1000 | 5000 | 100 |
| 2 | 20 | 2000 | 3000 | 200 |
| 3 | 20 | 1500 | 4000 | 150 |
6. Precautions
- Table positioning only supports the CPU body and does not support high-speed input/output pulse modules
- When using soft elements, select the power-off retention area
- The soft element addresses for each axis must not be duplicated
- Step operation must be triggered by an external signal to transfer rows via SM5580
7. References
- MELSEC iQ-F FX5 Programming Manual (Instructions, General FUN/FB Section)
- Basic Usage of Built-in Positioning Function of FX5U Series PLC
- Multi-Table Positioning Step Operation Based on FX5U