const { S7Endpoint, S7ItemGroup } = require('nodes7');

let plc = new S7Endpoint({ host: '192.168.0.1', rack: 0, slot: 1 });

plc.on('error', e => console.log('PLC Error!', e));
plc.on('disconnect', () => console.log('PLC Disconnect'));
plc.once('connect', async () => {
	console.log('connected!');

	// check the documentation for all available functions
	await plc.getTime(); //gets the PLC's current date/time
	await plc.blockCount(); //gets a count of blocks from the PLC of each type

	// you can use the S7ItemGroup to perform optimized read/write of variables

	let itemGroup = new S7ItemGroup(plc);

	let vars = {
		TEST1: 'MR4', 			// Memory real at MD4
		TEST2: 'M32.2', 		// Bit at M32.2
		TEST3: 'M20.0', 		// Bit at M20.0
		TEST4: 'DB1,REAL0.20',	// Array of 20 values in DB1
		TEST5: 'DB1,REAL4',		// Single real value
		TEST6: 'DB1,REAL8',		// Another single real value
		TEST7: 'DB1,INT12.2'	// Two integer value array
	}
	itemGroup.setTranslationCB(tag => vars[tag]); //translates a tag name to its address
	itemGroup.addItems(Object.keys(vars));

	console.log(await itemGroup.readAllItems());

	await plc.disconnect(); 	//clean disconnection
});