WebApi and PLC Node data reading and writing

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plc_read_node
plc_read_nodes
plc_write_node
plc_write_nodes

After configuring the http service, you can communicate with LECPServer through WebApi.

There are 4 interface action of communication commands, which are

plc_read_node read a single node
plc_read_nodes read multiple nodes
plc_write_node write a single node
plc_write_nodes write multiple nodes

The details of the interface are as follows

plc_read_node

Basic Information

read a single node

Interface status: normal
Interface URL: http://xxxxx:xxx
Request method: POST
Content-Type: application/json

Parameter description

name	type	description
action	string	command plc_read_node
node	string	Node name, in the form NODE.[dev].[node_name], such as NODE.MODBUS.C00

Return value description

name	type	description
errcode	int	Exception number, returns 0 if successful
errmsg	string	Exception information, if successful, return ""
rtval	object array	Return the values of the node as an array, the length of the array is the setting length of PLC node in LECPServer

Example

// send
{
	"action": "plc_read_node",
	"node": "NODES.MODBUS.C0000"
}

// response
{
	"errcode": 0,
	"errmsg": "",
	"rtval": [
		true,
		true,
		false,
		false,
		false
	]
}

plc_read_nodes

read multiple nodes

Basic Information

Interface status: normal
Interface URL: http://xxxxx:xxx
Request method: POST
Content-Type: application/json

Parameter description

name	type	description
action	string	command plc_read_nodes
node	string array	Nodes name, in the form of [ NODE.[dev].[node_name], NODE.[dev].[node_name]], such as [ "NODE.MODBUS.C00" , ""NODE.MODBUS.H00""]

Return value description

name	type	description
errcode	int	Exception number, returns 0 if successful
errmsg	string	Exception information, if successful, return ""
rtval	object array	Returns the values of all nodes in a two-dimensional array, the length of the array is the setting length of PLC node in LECPServer

Example

// send
{
	"action": "plc_read_nodes",
	"node": [
		"NODES.MODBUS.C0000",
		"NODES.MODBUS.H0000"
	]
}

// response
{
	"errcode": 0,
	"errmsg": "",
	"rtval": [
		true,
		true,
		false,
		false,
		false
	]
}

plc_write_node

write a single node

Basic Information

Interface status: normal
Interface URL: http://xxxxx:xxx
Request method: POST
Content-Type: application/json

Parameter description

name	type	description
action	string	command plc_write_node
node	string	Node name, in the form NODE.[dev].[node_name], such as NODE.MODBUS.C00
value	object array	The value of the node, as array, the length of the array is needs to be the same as the setting length of PLC node in LECPServer

Return value description

name	type	description
errcode	int	Exception number, returns 0 if successful
errmsg	string	Exception information, if successful, return ""

Example

// send
{
	"action": "plc_write_node",
	"node": "NODES.MODBUS.C0000",
	"value": [
		true,
		true,
		false,
		false,
		false
	]
}

// response
{
	"errcode": 0,
	"errmsg": ""
}

plc_write_nodes

write multiple nodes

Basic Information

Interface status: normal
Interface URL: http://xxxxx:xxx
Request method: POST
Content-Type: application/json

Parameter description

name	type	description
action	string	命令字 plc_write_nodes
node	string array	Nodes name, in the form of [ NODE.[dev].[node_name], NODE.[dev].[node_name]], such as [ "NODE.MODBUS.C00" , ""NODE.MODBUS.H00""]
value	object array	The value of the nodes, expressed as a two-dimensional array, such as [[v1-1,v1-2,v1-3,v1-4], [v2-1,v2-2,v2-3,v2,4]], The length of each subarray needs to be consistent with the PLC Node setting length of LECPServer

Return value description

name	type	description
errcode	int	Exception number, returns 0 if successful
errmsg	string	Exception information, if successful, return ""

Example

// send
{
	"action": "plc_write_nodes",
	"node": [
		"NODES.MODBUS.C0000",
		"NODES.MODBUS.H0000"
	],
	"value": [
		[
			true,
			true,
			false,
			false,
			false
		],
		[
			99,
			99,
			99,
			99,
			99
		]
	]
}

// response
{
	"errcode": 0,
	"errmsg": ""
}