Instruction Parameters
Supported PLC Series
| PLC-AES | PLC-FB | PLC-ES |
|---|---|---|
| ✓ | ✓ | ✓ |
Supported Data Registers
| M | X | Y | K | L | F | T | C | S | Z | R | Q | D | @D | Constant | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n | – | – | – | – | – | – | – | – | – | – | – | – | – | – | ✓ |
Supported Flags
| Flag | Bit | Support |
|---|---|---|
| Error | F11.0 | – |
| Zero | F11.1 | – |
| Carry | F11.2 | – |
Number of Steps
| Steps |
|---|
| 2 |
Operands
| Operand | Description |
|---|---|
| n | The only operand. Entries are only constants. This is the Interrupt Program ID number. The value range is 0 ~ 14. |
Notice
Instruction Behavior
The EI instruction behaves as follows:
- The Interrupt Program with the ID, n, will be enabled.
- The EI instruction enables execution of the interrupt programs that were disabled by the DI instruction.
- Once the EI instruction is executed, the enabled status is maintained.
Ladder Diagram Examples
EI
The EI instruction enables an interrupt program with the ID, n.
This is the periodic interrupt program for the ID 1.
When the contact, M1.0, is powered ON (1), the data register, D1, does NOT increase with the INCP instruction since the periodic interrupt program is NOT being executed in the main scan program.
This is the program for the ID 0, or main program.
When the contact, M0.0 is powered OFF (0), the EI instruction is not executing the periodic interrupt program with the ID 1 to enable it.
When the contact, M0.0 is powered ON (1), the EI instruction executes the periodic interrupt program with the ID 1 to enable it.
Since the EI instruction is executing the periodic interrupt program with the ID 1, the data register, D1, is increasing.