# Single Bit Data Read/Write Commands (01/05) (Commonly Used in HMIs)

[<sub><mark style="background-color:blue;">**Purpose and Use Cases:**<mark style="background-color:blue;"></sub> <sub><mark style="background-color:blue;"> </sub><sub><mark style="background-color:blue;">Certain Human-Machine Interfaces (HMIs) only support the<mark style="background-color:blue;"></sub> <sub><mark style="background-color:blue;"> </sub><sub><mark style="background-color:blue;">**05 Write Command**<mark style="background-color:blue;"></sub> <sub><mark style="background-color:blue;"> </sub><sub><mark style="background-color:blue;">to send a signal to<mark style="background-color:blue;"></sub> <mark style="background-color:blue;"></mark><mark style="background-color:blue;">reset the accumulated total. Additionally, some HMIs require support for the</mark> <mark style="background-color:blue;"></mark><mark style="background-color:blue;">**01 Read Command**</mark> <mark style="background-color:blue;"></mark><mark style="background-color:blue;">to verify that the sensor is functioning correctly.</mark>](#user-content-fn-1)[^1]

## **01 Command Example**

This command does **not reset** the **C02.Del.Total** (Clear Accumulated Total) option. It only provides the HMI with the ability to read Single Bit data using the 01/05 commands. If the command format is correct, the flow meter will respond to the master device with a Bit read acknowledgment.

#### **Control Terminal TX (Transmit) Command Example for 01**

| Byte#          | 1             | 2             | 3                                | 4                                | 5                   | 6                   | 7   | 8   |
| -------------- | ------------- | ------------- | -------------------------------- | -------------------------------- | ------------------- | ------------------- | --- | --- |
| Node ID        | Slave Address | Function Code | Starting Address of Data to Read | Starting Address of Data to Read | Data to Read (Bits) | Data to Read (Bits) | CRC | CRC |
| Example 01\~FF | 01            | 01            | 02                               | 01                               | 00                  | 01                  | AD  | B2  |

#### **Control Terminal TX (Transmit) Command Example for 01**

* **Slave Address:** `01` (Address of the flow meter)
* **Function Code:** `01` (1-bit Read Command)
* **Starting Address of Data to Read:** `02 01` (Start address for C02.Del.Total Clear Accumulated Total)
* **Data to Read (Bits):** `00 01` (Read C02.Del.Total data)
* **CRC:** `AD B2` (Error-checking code calculated using the CRC algorithm)

#### **Flow Meter RX (Receive) Response Example for 01**CommentShare feedback on the editor

| Byte#          | 1             | 2             | 3            | 4            | 5   | 6   |
| -------------- | ------------- | ------------- | ------------ | ------------ | --- | --- |
| Node ID        | Slave Address | Function Code | Response Bit | Response Bit | CRC | CRC |
| Example 01\~FF | 01            | 01            | 01           | 00           | 51  | 88  |

* \
  **Slave Address:** `01` (Address of the flow meter)
* CommentShare feedback on the editor**Function Code:** `01` (Read Command)
* CommentShare feedback on the editor**Response Bit:** `01 00` (The flow meter is still online and operational, responding to the control terminal)
* CommentShare feedback on the editor**CRC:** `51 88` (Error-checking code calculated using the CRC algorithm)

## **05 Command Example**

<mark style="background-color:blue;">This example activates the</mark> <mark style="background-color:blue;"></mark><mark style="background-color:blue;">**C02.Del.Total**</mark> <mark style="background-color:blue;"></mark><mark style="background-color:blue;">option to clear accumulated data, resetting the total to zero.</mark>

#### **Control Terminal TX (Transmit) Command Example for 05**

| Byte#          | 1             | 2             | 3                                 | 4                                 | 5             | 6             | 7   | 8   |
| -------------- | ------------- | ------------- | --------------------------------- | --------------------------------- | ------------- | ------------- | --- | --- |
| Node ID        | Slave Address | Function Code | Starting Address of Data to Write | Starting Address of Data to Write | Data to Write | Data to Write | CRC | CRC |
| Example 01\~FF | 01            | 05            | 02                                | 01                                | FF            | 00            | DC  | 42  |

* **Slave Address:** `01` (Address of the flow meter)
* **Function Code:** `05` (Register Write Command)
* **Starting Address of Data to Write:** `02 01` (Start address for C02.Del.Total Clear Accumulated Total)
* **Data to Write:** `FF 00` (Reset C02.Del.Total data)
* **CRC:** `DC 42` (Error-checking code calculated using the CRC algorithm)

#### **Flow Meter RX (Receive) Response Example for 05**tor

| Byte#          | 1             | 2             | 3                                 | 4                                 | 5             | 6             | 7   | 8   |
| -------------- | ------------- | ------------- | --------------------------------- | --------------------------------- | ------------- | ------------- | --- | --- |
| Node ID        | Slave Address | Function Code | Starting Address of Data to Write | Starting Address of Data to Write | Data to Write | Data to Write | CRC | CRC |
| Example 01\~FF | 01            | 05            | 02                                | 01                                | FF            | 00            | DC  | 42  |

* **Slave Address:** `01` (Address of the flow meter)
* **Function Code:** `05` (Register Write Command)
* **Starting Address of Data to Write:** `02 01` (Memory address for C02.Del.Total Clear Accumulated Total)
* **Data Written:** `FF 00` (Acknowledgment of reset action sent back to the control terminal)
* **CRC:** `DC 42` (Error-checking code calculated using the CRC algorithm)

[^1]:


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