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README_en.md

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+# Gidrolock Modbus Scanner
+
+[RU](https://github.com/nikzori/modbus-scanner) | EN
+
+A Modbus scanner with both simple functionality and advanced features. Comes with config files for Gidrolock devices.
+Modbus TCP is still WIP.
+
+## Configs and auto-identification
+
+Configs are `.json` files describing basic device info and data that can be polled from it. 
+The `checkEntry` object in the config allows to go through every config file in a folder to detect the appropriate config.
+
+## Regular polling
+
+This app can regularly and selectively poll entries from the config file. (Works, but still WIP)
+
+Config fields and possible values:
+
+```js
+{
+	// Template/device name
+	"name" : "Gidrolock Standard Wi-Fi RS-485",
+
+	// Device description
+	"description" : "Smart valve controller unit with wired and wireless leak sensor support",
+
+	// the list of entries that can be polled from the device
+	// each entry is a separate field that supports polling multiple registers and parsing data into UTF-8, int, etc.
+	"entries" : [
+		{
+			// entry name
+			"name": "Modbus ID",
+
+			// register type:
+			// "coil", "discrete", "input", "holding"
+			"registerType": "holding",
+
+			// starting register address 
+			// begins with 0
+			"address": 128,
+
+			// number of polled registers
+			// default value: 1
+			"length": 1,
+
+			// data type for parsing
+			// supported data types: bool, uint16, uint32, utf8
+			// default value: uint16
+			"dataType": "uint16",
+
+			// whether the entry should be polled again
+			// if `false`, the entry will be polled only once
+			"readOnce": true
+		}
+	],
+
+	// unique value for a device: model ID, firmware version
+	"checkEntry": {
+		"registerType": "input", 
+		"address": 200,
+		"length": 6,
+		"dataType": "string",
+		
+		// value after parsing
+		"expectedValue": "SWT485"
+	}
+}
+```
+
+
+### To-Do
+1. Cycle through configs in a folder to select a fitting one
+2. Configurable regular polling
+3. Modbus TPC support
+