Introduction
All Maple Systems HMI+PLCs (HMCs) programmed with MAPware7000 are compatible with Modbus RTU Slave (Server). Configure your Controller and HMI+PLC (HMC) with the following parameters to establish reliable communication.
Applies to: MAPware7000
Overview
MAPware7000 supports Modbus RTU. Maple Systems HMI + PLC (HMCs) communicate with any device that uses the Modbus RTU protocol. The HMC/PLC uses the Modbus RTU (Unit as Slave) protocol driver to allow the Maple device to act as a slave in a single master, single slave or multiple slave format.
HMI+PLC Settings
The table below lists the communications settings that must be configured in MAPware7000. These settings can be found in the Network Configuration folder for the selected project in the Project Information window:
Right-click the Com port that you will use to connect to the slave device, and then click Add… to display
the Node Information dialog box:
NOTE: The Recommended Settings column is blank since the Modbus RTU Slave Protocol can be used with any controller supporting Modbus RTU Master. The available port may determine whether RS-232 or RS-485 should be used.
The Options column lists MAPware7000 options; your PLC may not support every option
| Name | Recommended Setting | Options | Important Notes |
|---|---|---|---|
| Port | No recommended option | COM1, COM2, Ethernet | This is the HMC port that the PLC is connected to |
| Protocol | Modbus RTU (Unit as Slave) | No recommended option | Select the appropriate protocol for your PLC |
| Model | Modbus Slave | Varies depending on the selected protocol | Select the model that is most closely associated with your PLC |
| Communication Setting: Baud Rate | 19200 | 4800, 9600, 19.2k, 38.4k, 57.6k, 115.2k, 187.5k | Must match the PLC serial port |
| Communication Setting: Parity | None | None, Even, Odd | Must match the PLC serial port |
| Communication Setting: Data Bits | 8 | 7, 8 | Must match the PLC serial port |
| Communication Setting: Stop Bits | 2 | 1, 2 | Must match the PLC serial port |
| Power On PLC Communication Time | No recommended option | 0-255 seconds | Delays communications with the PLC after applying power to the HMC |
| Node Information: Name | No recommended option | Maximum of 15 characters | Provide a meaningful description to the port |
| Node Information: Address | 1 | 0 to 255 | Assigns a network address to each PLC. Use when networking several PLCs on one COM port. |
| Node Information: Inter frame Delay | No recommended option | 0 to 3000 msec | Minimum time delay between commands sent to the PLC |
| Node Information count | No recommended option | 0 to 5 | The maximum attempts by the HMC to resend unanswered command. |
| Node Information: Response Time Out | No recommended option | 10 to 6000 msec | The time that must pass before the HMC reattempts to send an unanswered command to the PLC |
Connected Device Settings
The Modbus port on the connected device must be set to RTU master mode in order to properly
communicate with the HMC slave.
In IEC 61131-3 projects, a Modbus address must be manually assigned to each tag in the Tag Database.
To access the Tag Database go to Define > Tag Database, or click on the Tags folder in the project tree.
Assign the Modbus address in the appropriate COM column of the Tag Database.
NOTE: Read Write access will be specified in the tag database. Most tags are Read/Write, tags defined for input modules and some system tags will be Read Only.
| Data Types | Length | Modbus Address Range | Notes |
|---|---|---|---|
| DINT, DWORD, REAL, TIME, UDINT | 2 Words (32-bits) | 400001 – 465534 | Note 1 |
| INT, Retentive Registers, WORD, UINT | 1 Word (16-bits) | 400001 – 465535 | |
| BYTE, SINT, USINT | 1 byte (8-bits) | 400001 – 465535 | Note 2 |
| BOOL | 1-bit | 000001 – 065535 |
NOTE 1: 32-bit types require two Modbus registers. The tag occupies the specified address and the next consecutive address. Tag addresses cannot overlap.
NOTE 2: 8-bit types require one Modbus address per tag. The data will reside in the low word of the register
Important note: Most Modbus Master Devices read blocks of data at a time; it is good practice to assign
consecutive Modbus addresses when using IEC Mode.
Important Memory Considerations
If your PLC memory range is smaller than the range supported by the Master Device, it is possible
to configure the unit to monitor PLC memory addresses that are not available. Because this can
cause unpredictable results, when you configure the Master Device, ensure that all selected PLC
memory addresses are valid for your PLC model.
Do not configure the Master device to write to any PLC memory address which should only be
written to by the PLC.
Wiring Diagram
The Maple HMC’s serial port connects directly to the communications port on the Master Device.
WARNING If your communications cable is not wired exactly as shown in our cable assembly
instructions, damage to the HMC or loss of communications can result.
Physical Port: 4.3″ Models
COM1: The 4.3″ models have 1 physical COM port that supports RS232 and RS485
Physical Ports: 7.0″ Models
COM1: Terminal Block Port – RS232 / RS485
COM2: DE9 Female Port – RS232 / RS485
Physical Ports: 10.1″ Models
COM1 & COM2: The 10.1″ models have 2 physical COM ports that both supports RS232 and RS485
Y Type Cable (all models)
- Special “Y” cable for HMC unit (two communication levels on one port)
RS-485 – 2 Wire (all models)
RS-485 – 4 Wire (all models)
