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 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n1 | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | – | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| n2 | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | – | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| D | ✓ | – | ✓ | ✓ | ✓ | – | ✓ | ✓ | – | ✓ | – | ✓ | ✓ | ✓ | ✓ |
| n3 | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | – | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
Supported Flags
| Flag | Bit | Support |
|---|---|---|
| Error | F11.0 | ✓ |
| Zero | F11.1 | – |
| Carry | F11.2 | – |
Number of Steps
| Steps |
|---|
| 5 |
Operands
| Operand | Description |
|---|---|
| n1 | The first operand. Entries are Hexadecimal WORD data registers or constants. This is the base and slot number of the expansion module to read from. This number depends on the amount of expansion modules the chassis contains. |
| n2 | The second operand. Entries are DWORD data registers or constants. This is the address of buffer memory where the data is read from. The value range depends on the buffer memory to read from. |
| D | The third operand. Entries are only DWORD data registers. This is the storage location, on the CPU module, for the data being read. |
| n3 | The fourth operand. Entries are DWORD data registers or constants. This is the amount of DWORD data to read. The value range is 0 ~ 255. |
Assignment Example
The following example shows how to assign values to n1 and Base/Slot.
n1
| Base Number | Slot Number | |
|---|---|---|
| H | 0A | 0B |
| Hexadecimal | 2 Digits in Hexadecimal | 2 Digits in Hexadecimal |
PLC-AES/ES
The base number and slot number depend on the chassis type. Since the PLC chassis can only go up to 11 or 15 expansion modules, the base number is always 00.
Module/Slot (PLC-AES/ES)
| Module | Slot | Example |
|---|---|---|
| CPU | Slot 0 | H0000 or 0 |
| 1st Expansion | Slot 1 | H0001 or 1 |
| 5th Expansion | Slot 5 | H0005 or 5 |
| 10th Expansion | Slot 10 | H000A |
| 15th Expansion | Slot 15 | H000F |
Notice
Error Flag (F11.0) Notice
The error flag, F11.0, will be ON for one scan when the address of the data register assigned by @D exceeds the range of the data register, D. The range of the data register, D, is dependent on the CPU type. F11.0 turns ON when access to the expansion module fails. F11.0 turns ON when the base and slot number assigned to n1 is not an expansion module. F11.0 turns ON when the number of data in n3 exceeds the range of the data register assigned to D.
Execution Condition
It is recommended that the DFRO instruction be used with a pulse contact as an execution condition, or use the DFROP instruction.
Ladder Diagram Examples
DFRO
The DFRO instruction reads n3 number of DWORD data from the buffer memory address, n2, on the expansion module, n1, into the assigned DWORD data register, D.
When the contact, M2.0 is ON (1), 1 DWORD value of the buffer memory 3 is read from the expansion module at slot H0003 and stored in the data register, D5.
In this example, 260,898,815 is read from the precise value (channel 2) buffer memory of the IO-SA0202Y expansion module at slot 3.
Memory Monitor
DFROP
The DFROP one-shot instruction reads n3 number of DWORD data from the buffer memory address, n2, on the expansion module, n1, into the assigned DWORD data register, D. Every time this instruction executes, it energizes the output only once.
When the contact, M3.0 is ON (1), 1 DWORD value of the buffer memory 2 is read from the expansion module at slot H0004 and stored in the data register, D10.
In this example, 24.1°C (digital value: 241) is read from the temperature detection value (°C) (channel 2) buffer memory of the IO-SA0400 expansion module at slot 4.
Memory Monitor
