text: 
  module.exports = function(RED) {
      "use strict";
      var fs = require('fs');
      var allOK = false;
      var mcpadc;
      // unlikely if not on a Pi
      try {
          var cpuinfo = fs.readFileSync("/proc/cpuinfo").toString();
          if (cpuinfo.indexOf(": BCM") === -1) {
              RED.log.warn("Info : mcp3xxx : Not running on a Pi - Ignoring node");
          }
          else {
              mcpadc = require('mcp-spi-adc');
              allOK = true;
          }
      }
      catch(err) {
          RED.log.warn("Info : mcp3xxx : Not running on a Pi - Ignoring node");
      }
  
      //var mcp3xxx = [];
  
      function PiMcpNode(n) {
          RED.nodes.createNode(this,n);
          this.pin = n.pin || 0;
          this.interval = n.interval || 1000;
          this.dnum = parseInt(n.dnum) || 0;
          this.bus = parseInt(n.bus) || 0;
          this.dev = n.dev || "3008";
          this.mcp3xxx = [];
          this.cb = function (err) { if (err) { node.error("Error: "+err); } };
          this.opt = { speedHz:20000, deviceNumber:this.dnum, busNumber:this.bus };
          var chans = parseInt(this.dev.substr(3));
          var node = this;
  
          if (allOK === true) {
              try {
                  fs.statSync("/dev/spidev"+node.bus+"."+node.dnum);
                  if (node.mcp3xxx.length === 0) {
                      for (var i=0; i<chans; i++) {
                          if (node.dev === "3002") { node.mcp3xxx.push(mcpadc.openMcp3002(i, node.opt, node.cb)); }
                          if (node.dev === "3004") { node.mcp3xxx.push(mcpadc.openMcp3004(i, node.opt, node.cb)); }
                          if (node.dev === "3008") { node.mcp3xxx.push(mcpadc.openMcp3008(i, node.opt, node.cb)); }
                          if (node.dev === "3201") { node.mcp3xxx.push(mcpadc.openMcp3201(i, node.opt, node.cb)); }
                          if (node.dev === "3202") { node.mcp3xxx.push(mcpadc.openMcp3202(i, node.opt, node.cb)); }
                          if (node.dev === "3204") { node.mcp3xxx.push(mcpadc.openMcp3204(i, node.opt, node.cb)); }
                          if (node.dev === "3208") { node.mcp3xxx.push(mcpadc.openMcp3208(i, node.opt, node.cb)); }
                          if (node.dev === "3304") { node.mcp3xxx.push(mcpadc.openMcp3304(i, node.opt, node.cb)); }
                      }
                  }
                  node.on("input", function(msg) {
                      var pin = null;
                      if (node.pin === "M") {
                          var pay = parseInt(msg.payload.toString());
                          if ((pay >= 0) && (pay < chans)) { pin = pay; }
                          else { node.warn("Payload needs to select channel 0 to "+(chans-1)); }
                      }
                      else { pin = parseInt(node.pin); }
                      if (pin !== null) {
                          node.mcp3xxx[pin].read(function (err, reading) {
                              if (err) { node.warn("Read error: "+err); }
                              else { node.send({payload:reading.rawValue, topic:"adc/"+pin}); }
                          });
                      }
                  });
              }
              catch(err) {
                  node.error("Error : Can't find SPI device - is SPI enabled in raspi-config ?"+ err);
              }
  
              node.on("close", function(done) {
                  if (node.mcp3xxx.length !== 0) {
                      var j=0;
                      for (var i=0; i<chans; i++) {
                          node.mcp3xxx[i].close(function() { j += 1; if (j === chans) {done()} });
                      }
                      node.mcp3xxx = [];
                  }
                  else { done(); }
              });
          }
          else {
              node.status({text:"node inactive."})
          }
      }
  
      RED.nodes.registerType("pimcp3008",PiMcpNode);
  }
  