What This Gateway Does
O G1003 HART to Modbus gateway connects HART devices para Modbus networks. It’s a protocol converter that works in the opposite direction to the G0310. The G0310 takes Modbus data and puts it onto HART. The G1003 takes HART data and makes it available to Modbus systems.
On the HART side, the gateway acts as a HART master. It polls HART slave devices (transmitters, valves, analyzers) and reads their data. On the Modbus side, the gateway acts as a Modbus slave, responding to requests from a Modbus master (PLC, DCS, or SCADA).
This means you can take existing HART instruments and bring their data into a Modbus-based control system without replacing any hardware.
For detailed configuration examples, refer to the G1003 configuration guide.
Who Uses It
System integrators connecting HART devices to Modbus networks. Plant engineers who need to bring HART instrument data into older Modbus-based control systems. Anyone running mixed protocol environments where HART instruments need to feed data into a Modbus PLC or SCADA.
The gateway also acts as a HART modem when needed, making it useful for temporary connections and diagnostics.
Four Working Modes
The G1003 has four operating modes, selected by a two-digit DIP switch on the front panel:
Normal working mode (MC: OFF, OFF):
- Default mode after configuration
- HART channel polls configured slave devices and stores data in internal memory
- Modbus channel responds to requests from Modbus master
- Supports non-cyclic HART commands through Modbus channel
HART Modem mode (MC: OFF, ON):
- Gateway acts as a HART modem
- Passes all data between HART master system and HART slave network
- Modbus channel forwards data using fixed HART communication parameters (1200 bps, 8 data bits, odd parity, 1 stop bit)
Configuration mode (MC: ON, OFF):
- All gateway parameters can be configured through configuration software
- HART channel does not work
- Modbus channel uses fixed communication parameters (address 1, 19200 bps, 8 data bits, even parity, 1 stop bit, CRC low byte first)
Debugging mode (MC: ON, ON):
- Both HART and Modbus channels work normally
- Allows viewing all gateway parameters through configuration software
- Useful when no Modbus master system is available
- Modbus channel uses same fixed parameters as configuration mode
After changing the mode, power cycle the gateway for the change to take effect.
For instructions on switching modes, see the G1003 installation guide.
HART Channel Overview
The G1003 supports one HART channel that operates as the first or second master station on the HART network. It actively sends HART commands to configured slave devices and stores the response data in the gateway’s internal data area.
Automatic polling mode (enabled by default):
The gateway automatically sends HART commands 0, 3, 13, 14, and 15 to configured slave devices:
- Command 0: Read unique identifier (long address, manufacturer ID, etc.)
- Command 3: Read loop current and four dynamic variables
- Command 13: Read tag, descriptor, and date
- Command 14: Read sensor information
- Command 15: Read transmitter output information
The gateway can manage up to 16 HART slave devices (short addresses 0-15). Each device gets 102 bytes of data storage.
Custom HART commands:
Users can configure up to 100 custom HART commands. Each command can be set to:
- Initialize output: Sent once when the gateway powers on and the device is online
- Polling output: Sent periodically
- Change output: Sent when data in the send buffer changes
- No output: Not sent automatically (can be triggered manually)
Non-cyclic HART communication:
The gateway also supports sending non-cyclic HART commands through the Modbus channel. The Modbus master sends a request with HART command parameters, the gateway forwards it to the HART network, and stores the response for the Modbus master to read.
For more details on HART command configuration, visit the G1003 HART configuration page.
Modbus Channel Overview
The Modbus channel operates as a slave station, responding to requests from a Modbus master system. It supports both Modbus RTU e Modbus ASCII communication modes.
Hardware interfaces:
- RS232
- RS485
- RS422
All three interfaces share the same Modbus channel. They can be connected simultaneously but cannot communicate at the same time.
Communication parameters (configurable):
| Parâmetro | Options |
|---|---|
| Baud rate | 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 bps |
| Data bits | 7 or 8 (8 for RTU mode) |
| Parity | None, Even, Odd |
| Stop bits | 1 or 2 |
| CRC byte order | Normal (high byte first) or Exchange (low byte first) |
| Node address | 1-247 |
| Communication mode | RTU or ASCII |
Default communication parameters (configuration/debug mode):
- Address: 1
- Baud rate: 19200 bps
- Data bits: 8
- Parity: Even
- Stop bits: 1
- CRC byte order: Low byte first
Internal Data Area
The gateway has a shared internal data area accessible by both HART and Modbus channels.
Data areas:
| Area | Register Range | Usage |
|---|---|---|
| HART slave basic data | 3500+ | Data from automatic polling mode (commands 0, 3, 13, 14, 15) |
| Custom command input | 2000-6999 | Response data from custom HART commands |
| Custom command output | 2000-6999 | Data to send with custom HART commands |
| Non-cyclic data | 5000+ | Temporary storage for non-cyclic HART communication |
Each HART slave device (address 0-15) has 51 registers (102 bytes) of basic data. Register address calculation: 3500 + 51 × polling address + register offset.
Data includes:
- Manufacturer ID
- Device type
- Device ID
- Tag, descriptor, date
- Primary variable, secondary variable, tertiary variable, quaternary variable (floating point values)
- Sensor upper/lower limits
- Range upper/lower values
- Damping value
If a HART slave device goes offline, the gateway retains the last data received before the power loss.
For a complete register map, refer to the G1003 memory map documentation.
Configuration Software
The G1003 is configured using the Ferramenta de Configuração Geral Modbus provided by Microcyber.
Instalação:
- Download the latest version from the Microcyber website
- Run Modbus General Configuration tool.exe
- Follow the installation prompts
Starting the software:
- Double-click the desktop icon
- Or find it in the Start menu
- The main interface appears as shown in the manual
Main interface components:
- Menu Bar: File, Tools (language settings), Help
- Toolbar: Search devices, Cancel search, Batch download, Print
- Device List: Tree view of serial ports and devices
- Device Information: Manufacturer ID, device type, protocol type
- Parameter Area: Configuration parameters displayed in table form
- File Library: XML files for saving/loading configurations
- Operation Tips: Status and guidance messages
For step-by-step software setup, visit the G1003 configuration software page.
Configuration Steps
1. Set gateway to configuration mode:
| DIP Switch | Position |
|---|---|
| Bit 1 | ON |
| Bit 2 | OFF |
2. Connect hardware:
- Connect RS232 (or RS485/RS422) to computer serial port
- Power on the gateway
- Power LED (PW) should be on
3. Configure software connection:
- Start configuration software
- Right-click “Host” → “Add Serial Port”
- Select the serial port connected to the gateway
- Move it to “Selected Port” and confirm
- Right-click the serial port → “Search Device”
4. Configure Modbus parameters (Modbus configuration data):
- Baud rate, data bits, parity, stop bits, CRC byte order, node address, communication mode
- Click “Download The Current Page Parameters” to save
5. Configure HART parameters (HART configuration data):
- Network mode (single-point or multi-point)
- Master station type (first or second master)
- Short address list (which HART devices to poll)
- Number of leading characters (2-20)
- Retry count
- Click “Download The Current Page Parameters” to save
6. Configure custom HART commands (custom command configuration data):
- Click “Add” to add a command
- Set short address, command number, output mode
- Set send buffer start address and length
- Set receive buffer start address and length
- Click “Modify” to save
- Click “Automatic address mapping” to assign addresses
- Click “Conflict detection” to check for conflicts
- Click “Download The Current Page Parameters” to save
7. Return to normal mode:
- Set DIP switches to OFF, OFF
- Power cycle the gateway
8. Verify operation:
- Use Modbus master simulation software to read data from the gateway
- Check HART device online status
- Verify custom command responses
Supported Modbus Function Codes
| Código | Operation |
|---|---|
| 0x03 | Read holding registers |
| 0x04 | Read input registers |
| 0x06 | Write single register |
| 0x10 | Write multiple registers |
Technical Specifications
| Parâmetro | Especificação |
|---|---|
| Fonte de alimentação | 9-30 VDC |
| Power consumption | ≤1W |
| HART interface | Digital HART signal, ≥5kΩ input impedance, 50V withstand voltage |
| HART output amplitude | 500mVpp (at 500Ω) |
| Tensão de isolamento | 500V AC between Modbus and HART |
| Temperatura de operação | -20°C to 70°C |
| Temperatura de armazenamento | -20°C to 70°C |
| Umidade | 5-95% RH |
| Proteção | IP20 |
| Peso | 0.2 kg |
| Material de construção | ABS/PA66 |
Default Communication Parameters
| Mode | Baud Rate | Data Bits | Parity | Stop Bits |
|---|---|---|---|---|
| Normal/Configuration/Debug | 19200 | 8 | Even | 1 |
| HART Modem | 1200 | 8 | Odd | 1 |
LED Indicators
| LED | Color | Normal Status | Significado |
|---|---|---|---|
| PW | Yellow | On | Power is on |
| HT | Yellow/Green | Flickering | HART communication active |
| MB | Yellow/Green | Flickering | Modbus communication active |
Troubleshooting
| Problem | Causa Possível | Solução |
|---|---|---|
| PW LED off | Power failure | Check power and connections |
| HT LED off | Wrong configuration | Check HART parameters, check gateway mode |
| HT LED off | Gateway in config mode | Switch to normal mode |
| MB LED off | No Modbus connection | Check Modbus wiring and master device |
| Configuration software can’t find device | Incorrect serial port | Check COM port selection |
| Configuration software can’t find device | Gateway not powered | Check power supply |
For additional support, contact Microcyber technical support.
Ordering Information
| Produto | Descrição |
|---|---|
| G1003 | HART master to Modbus slave gateway |
About Microcyber
Microcyber was founded by the Shenyang Institute of Automation, Chinese Academy of Sciences. The company developed the first internationally approved FF H1 protocol stack in China and participated in drafting the EPA standard (now an IEC international standard). Microcyber is a member of FCG and PNO, and holds ISO 9001 certification.
