9,546
edits
Changes
Template:Networking rutos manual modbus (view source)
Revision as of 12:26, 28 December 2021
, 12:26, 28 December 2021no edit summary
----
----
A Modbus <b>request</b> is a way of obtaining data from Modbus slaves. The master sends a request to a slave specifying the function code to be performed. The slave then sends the requested data back to the Modbus master. You can create a maximum of 64 request configurations for each slave device.
A Modbus <b>request</b> is a way of obtaining data from Modbus slaves. The master sends a request to a slave specifying the function code to be performed. The slave then sends the requested data back to the Modbus master. You can create a maximum of 64 request configurations for each slave device.
<span style="color:red"> <b>Note: </b></span> Modbus TCP Master uses <i>Register Number</i> instead of <i>Register Address</i> for pointing to a register. For example, to request the <i>Uptime</i> of a device, you must use <b>2</b> in the <i>First Register</i> field.
The Request Configuration list is empty by default. To add a new Request Configuration loon to the Add New Instance section. Enter a custom name into the 'Name' field and click the 'Add' button:
The Request Configuration list is empty by default. To add a new Request Configuration loon to the Add New Instance section. Enter a custom name into the 'Name' field and click the 'Add' button:
----
----
A Modbus <b>request</b> is a way of obtaining data from Modbus slaves. The master sends a request to a slave specifying the function code to be performed. The slave then sends the requested data back to the Modbus master. You can create a maximum of 64 request configurations for each slave device.
A Modbus <b>request</b> is a way of obtaining data from Modbus slaves. The master sends a request to a slave specifying the function code to be performed. The slave then sends the requested data back to the Modbus master. You can create a maximum of 64 request configurations for each slave device.
<span style="color:red"> <b>Note: </b></span> Modbus Serial Master uses <i>Register Number</i> instead of <i>Register Address</i> for pointing to a register. For example, to request the <i>Uptime</i> of a device, you must use <b>2</b> in the <i>First Register</i> field.
The Request Configuration list is empty by default. To add a new Request Configuration loon to the Add New Instance section. Enter a custom name into the 'Name' field and click the 'Add' button:
The Request Configuration list is empty by default. To add a new Request Configuration loon to the Add New Instance section. Enter a custom name into the 'Name' field and click the 'Add' button:
----
----
A Modbus <b>request</b> is a way of obtaining data from Modbus slaves. The master sends a request to a slave specifying the function code to be performed. The slave then sends the requested data back to the Modbus master. You can create a maximum of 64 request configurations for each slave device.
A Modbus <b>request</b> is a way of obtaining data from Modbus slaves. The master sends a request to a slave specifying the function code to be performed. The slave then sends the requested data back to the Modbus master. You can create a maximum of 64 request configurations for each slave device.
<span style="color:red"> <b>Note: </b></span> Modbus Serial Master uses <i>Register Number</i> instead of <i>Register Address</i> for pointing to a register. For example, to request the <i>Uptime</i> of a device, you must use <b>2</b> in the <i>First Register</i> field.
The Request Configuration list is empty by default. To add a new Request Configuration loon to the Add New Instance section. Enter a custom name into the 'Name' field and click the 'Add' button:
The Request Configuration list is empty by default. To add a new Request Configuration loon to the Add New Instance section. Enter a custom name into the 'Name' field and click the 'Add' button:
===Request messages===
===Request messages===
----
----
<span style="color:red"> <b>Note: </b></span>MQTT Gateway uses <i>Register Number</i> instead of <i>Register Address</i> for pointing to a register. For example, to request the <i>Uptime</i> of a device, you must use <b>2</b> in the <i>Register Number</i> field.
Modbus request data sent in the MQTT payload should be generated in accordance with the following format:
Modbus request data sent in the MQTT payload should be generated in accordance with the following format:
<li><b>16</b> - write to multiple holding registers.</li>
<li><b>16</b> - write to multiple holding registers.</li>
</ul></li>
</ul></li>
<li><b>Register number</b> - number of the first register (in range [1..65536]) from which the registers will be read/written to.
<li><b>Register number</b> - number (not address) of the first register (in range [1..65536]) from which the registers will be read/written to.
<li><b>Register count/value</b> - this value depends on the Modbus function:
<li><b>Register count/value</b> - this value depends on the Modbus function:
<ul>
<ul>
