Mitsubishi MC Protocol driver

Connecting to MELSEC-Q / L, iQ-R and iQ-F PLCs with MC Protocol (3E frame, Ethernet) and reading and writing with device addresses (D100, M10, X1F).

When to use it

The MC Protocol driver communicates with Mitsubishi MELSEC-Q / L, iQ-R and iQ-F (FX5U) PLCs over Ethernet using the 3E frame (TCP, default port 5007). An address consists of a device letter and a number: D100, M10, X1F. Serial (FX / A protocol) connections and 1E / 4E frames are not supported.

Prerequisites on the PLC side

• In the Ethernet settings of the PLC, a TCP connection must be opened for MC Protocol (SLMP); the port number in the connection is the same as the Port in Studio.
• If Binary or ASCII is selected in the PLC for the Data code (Communication Data Code), the Data code in Studio must be the same. If they do not match, the driver reports it with a message.
• To write while the PLC is in RUN state, Enable online change must be enabled in the Ethernet setting; if it is disabled, the write is rejected.
• It cannot be accessed if the PLC is locked with a remote password.

Setting up a connection

1. Add a connection

   In the Connections section: Add, driver Mitsubishi MC Protocol; enter the IP address and match the port to the connection in the PLC (default 5007).

2. Enter the parameters

   

   PLC series

   MELSEC-Q / L (default), MELSEC iQ-R or MELSEC iQ-F (FX5U). In the iQ-F series the X / Y numbers are written in octal, in the others in hexadecimal.

   Data code

   Binary (default) or ASCII; it must match the PLC setting.

   Network number

   0 – 239. 0 = directly connected PLC.

   PC number

   0 – 255. 255 = directly connected PLC.

3. Add a tag

   Enter the device and the number as the address (Tag addresses).

Devices and addresses

• D100.5: bit of the word device (0 – F, hexadecimal); used for a Bool tag. No separate bit number is written for bit devices.
• A Bool tag is linked to a bit device (M, X, Y …) or to a word-bit address; numeric types require a word device.
• For ambiguous notations such as SB10, the two-letter device (SB) is tried first.
• Int / UInt occupy 1 word, DInt / UDInt / Real occupy 2 words (low word first), LReal occupies 4 words. String holds 2 characters per word (the low byte of the word is the first character); the default Length is 32, maximum 254.
• The upper limit of the device number varies with the series and the data code; a number that is too large is rejected in Studio with the message The device number is larger than this frame can carry.

Read and write

• Nearby tags on the same device are read in a single request: at most 960 points in word units, at most 3584 points in bit units (half of that in ASCII code); gaps of at most 32 words (256 for bits) between them are merged.
• If the PLC rejects a block (device out of range), the block is read tag by tag; only the problematic tag gets an error.
• When a bit of a word is written, the word is read, the bit is changed and the word is written back.

Driver reference

Mitsubishi MC Protocol

MC Protocol 3E frame (MELSEC-Q / L, iQ-R, iQ-F). The port must be opened in the PLC's Ethernet settings. 32-bit types use two consecutive registers.

Driver ID

mc (name in the project file)

Connection

An IP address / computer name and a port are required (default port 5007)

Data types

Bool Int UInt DInt UDInt Real LReal String

Connection parameters

Appears in the Inspector window when a connection is selected.

Address formats

Sample addresses

Common errors

The marker at the start of each line tells where the message will appear in Live: [connection] in the Connections section of the system menu; [write] in the notification window of the operator who performed the write; [Studio] in the address cell in Studio. [tag] is a tag error during reading: the tag is left with bad quality, the text of the message is not shown in Live in this version (Tag errors); read the text to understand the cause.

Limits