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@rockos /plcsrv.js
Last active Dec 16, 2015

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Server program which simulates PLC(programmable logical controller for Mitsubishi elec.)
#!/usr/bin/env node
var redis = require("redis"),
client = redis.createClient();
var net = require('net');
var HOST = '127.0.0.1';
var PORT = 3011;
function log(objs) {
var d = new Date,
fmtDate = '',
month;
var msg = {};
month = d.getMonth() + 1;
fmtDate = d.getFullYear() + '/' + month + '/' + d.getDate() +
' ' + d.getHours() + ':' + d.getMinutes() + ':' +
d.getSeconds() + ':' + d.getMilliseconds();
console.log(fmtDate + ' ' + objs.title+':'+objs.info);
}
/**
*
*
*/
function readDB(name, num, cb) {
client.get('PLC-SRC',
function(err, reply) {
cb(err, reply);
});
}
/**
* format
* src
* 0123456789012345678901234567890
* 01FF000A4420rrrrrrrrnn00
* r: start address of device (08x)
* n: number of device (02x)
* repl
* 0123456789012345678901234567890
* 8100aaaabbbbcccc...SS
* a,b,..: value of each device (04s)
* S: check sum (02x)
*/
function formatData(stream, src, cb) {
var buf = '';
var head = '8100';
var devstrt = parseInt(src.slice(12, 20));
var devnum = parseInt(src.slice(20, 22), 16);
repl = '';
repllen = devnum*4 + 4;
readDB(devstrt, devnum, function(err, data) {
if (err) {
console.log('plcmon error occured: '+ err);
}
buf = data.slice(0, devnum*4);
repl += head + buf + 'EE';
// log({'title':'readDb','data':repl});
cb(stream, repl);
});
}
function sendTo(to, data) {
to.write(data);
log({'title':'send', 'info':data});
}
/**
*
*/
function recvFrom(stream, data) {
var repl = '';
var len = 0;
log({'title':'recv', 'info':data});
if (data.slice(0, 2) == '01') {
formatData(stream, data, sendTo);
} else {
sendTo(stream, '8300');
}
}
/**
*
*/
var server = net.createServer(function(stream) {
log({'title':'server', 'info':'connected'});
stream.on('data', function(data) {
recvFrom(stream, data);
});
stream.on('end', function() {
log({'title':'server', 'info':'disconnected'});
});
});
//server.listen(PORT, HOST, function() { //'listening' listener
server.listen(PORT, function() { //'listening' listener
console.log('server bound on port '+ PORT);
});
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