+++
title = "Modbus"
weight = 4
categories = "Modbus"
+++

# Modbus - Documentation

## Common

The controller exposes a Modbus 'Master' at the specified TCP interface on port 502.

There are dedicated registers for the VFD, PIDs and internal values.

## System Registers

| Name | Component ID  | Address | RW |  Function Code | Value |Register Description|
|------|----------|----|----|----|----|-------|
| System | 1 | 9 | -W | 0x6 | 1 | Print Modbus Queue  |
| System | 1 | 9 | -W | 0x6 | 2 | Print Component Modbus Registers  |
| System | 1 | 100 | -W | 0x6 | 1 | Reset Controller  |
| System | 1 | 19 | -W | 0x6 | 1 | Print PID controller states  |

**Remarks**

- Implementation for these calls : short ModbusBridge::loop() ./ModbusBridge.cpp
- It requires a USB cable connected, with 19200 bauds, 8 bits, no parity and 1 stop bit. You  can use Arduino's 'Serial Monitor' to see the output.

## VFD Registers

The VFD (Omron - MX2) is being polled and controlled via RS485 at a defined Modbus slave address (Default `1`). See more about the setup [here](../installation/).

| Name | Component ID  | Address | RW |  Function Code | Value |Register Description|
|------|----------|----|----|----|----|-------|
| VFD | 200 | 5 | -W | 0x6 | 1 | Set VFD in `RUN` mode  |
| VFD | 200 | 5 | -W | 0x6 | 2 | Set VFD in `STOP` mode  |
| VFD | 200 | 5 | -W | 0x6 | 3 | Set VFD in `RETRACT` mode (stop and retract)  |
| VFD | 200 | 6 | -W | 0x6 | 0-100 | VFD Target Frequency  |
| VFD | 200 | 2 | -R | 0x6 | 0-100 | VFD Current Monitor  |
| VFD | 200 | 3 | -R | 0x6 | - | **VFD Status** <br/>`OMRON_STATUS_STOPPED=2` <br/> `OMRON_STATUS_RUNNING=0`  |
| VFD | 200 | 4 | -R | 0x6 | - | **VFD State** <br/>`OMRON_STATE_ACCELERATING=4`<br/> `OMRON_STATE_DECELERATING=2` <br/>`OMRON_STATE_RUNNING=3` <br/> `OMRON_STATE_STOPPED=1` <br/> `OMRON_STATE_ERROR=8`   |

## PID Registers

The PID controllers (Omron - EDC5) are being polled and controlled via RS485 at a defined Modbus slave address, starting by default from `4`. 

| Name | Component ID  | Address | RW |  Function Code | Value |Register Description|
|------|----------|----|----|----|----|-------|
| PID | 100 | 20 | R- | 0x6 | 0-Maximum Temperature (`PV`) | PID-0 Temperature  |
| PID | 100 | 21 | R- | 0x6 | 0-Maximum Temperature / Set Point | PID-0 Set Point (`SP`)  |
| PID | 100 | 22 | R- | 0x6 | Status | PID-0-Status / Default State : 'Is Heating'  |
| PID | 100 | 23 | R- | 0x6 | 0-Maximum Temperature (`PV`) | PID-1 Temperature  |
| PID | 100 | 24 | R- | 0x6 | 0-Maximum Temperature / Set Point | PID-1 Set Point (`SP`)  |
| PID | 100 | 25 | R- | 0x6 | Status | PID-1-Status / Default State : 'Is Heating' |

## Auxillary Registers (Sensors / Switches)

| Name | ID  | Address | RW |  Function Code | Number Addresses |Register Description|
|------|----------|----|----|----|----|-------|
| OmronPID | 100 | 20 | R- | 0x6 | 6 |  |
| MB_Relay | 300 | 41 | RW | 1 | 1 |  |
| MB_Relay | 301 | 42 | RW | 1 | 1 |  |
| POT | 400 | 51 | R- | 3 | 1 |  |
| POT | 401 | 52 | R- | 3 | 1 |  |
| Pos3Analog | 501 | 61 | R- | 3 | 1 | - Read Position : Address=61(3D) -> [Up:1  Middle:0 Down:2] |
| Pos3Analog | 502 | 62 | R- | 3 | 1 | - Read Position : Address=62(3E) -> [Up:1  Middle:0 Down:2] |
| VFD | 200 | 5 | -- | 3 | 1 |  |
| Stepper | 601 | 70 | RW | -1 | 4 |  |
| MotorLoad | 210 | 2 | R- | 3 | 1 |  |
| Status - LED | 701 | 84 | RW | 3 | 1 |  |
| Status - LED | 702 | 85 | RW | 3 | 1 |  |

### Stepper

| Name | ID  | Address | RW |  Function Code | Value |Register Description|
|------|----------|----|----|----|----|-------|
| Stepper-0 | 601 | 70 | RW | 0x6 | 0-5000 | Stepper-Speed|
| Stepper-0 | 601 | 71 | RW | 0x6 | 0-1 | Stepper-Direction |
| Stepper-0 | 601 | 72 | R- | 0x6 | - | Stepper-Status |
| Stepper-0 | 601 | 72 | -- | 0x6 | - | Stepper-User |

### Feed - Servo

| Name | ID  | Address | RW |  Function Code | Value |Register Description|
|------|----------|----|----|----|----|-------|
| Feed - VFD - Ratio | 601 | 16 | -W | 0x6 | 0-100 | Stepper-Speed|

The servo is turned on automatically as soon the VFD starts running.

## Tools

To monitor and control the system, please open [printhead-poll.mbp](tools/printhead-poll.mbp) with [MbPoll_v9.4.0.exe](tools/MbPoll_v9.4.0.exe)

![Example](mpoll-registers.jpg)
 [Google Sheet](https://docs.google.com/spreadsheets/d/1l9LVWKOTbPbWQlEmDhRZYHpJaKBwTFTC-T0idTb0_fc/edit?usp=sharing)

## Simulate Modbus for Development

- Please use [MbSlave_v7.3.0.exe](tools/MbSlave_v7.3.0.exe) to start a Modbus-RTU master on TCP. You can use the ModbusPoll app to verify your code.

## References

- [Modbus Poll Registers - 0 to 100 - GoogleSheet](https://docs.google.com/spreadsheets/d/1l9LVWKOTbPbWQlEmDhRZYHpJaKBwTFTC-T0idTb0_fc/edit?usp=sharing)
- [Omron - E5DC Documentation](vendor/omron/e5dc/h174_e5_c_-_digital_temperature_controllers_users_manual_en.pdf)
- [Omron - E5DC Communication Documentation](vendor/omron/e5dc/h175_e5_c_communications_manual_en.pdf)
- [Omron - MX2 Documentation](vendor/omron/mx2/I570-E2-02B.pdf)
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