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ArduinoWaker

 

This page's comments/discussion on Arduino Forum: ArduinoWaker - discussion

Now with image gallery! :) Please check ArduinoWaker-Images

 

Introduction

This is a 'proof-of-concept' writeup, which uses Arduino + Arduino Ethernet Shield to assist with management of remote PCs.

The code, ArduinoWaker.pde, is based on Sdfrethsh shell, and can also be found on SourceForge.net Repository - (sdaaubckp) Index of /sdfrethsh - v.1.0.0 is also included below for reference.

Disclaimer: Since the concept described here deals with switching mains voltage for computers, needless to say, physical damage and loss is possible; so just to repeat - there is no warranty whatsoever regarding the code and procedure described below; experiment with this at your own risk :)

ArduinoWaker assembled (prototype)
ArduinoWaker prototype assembled

 

Context

''Say you have a PC that you have to manage remotely, and it's quite far away. Of course, you start thinking about remote management - and after some trouble, you manage to install something like VNC and do your thing remotely. So far, so good.

Then the PC crashes, and you have to either nag someone to push a button on the computer to start it up again, or you have to go there and do that yourself :) Then you decide to read up on Wake on Lan, and after making sure everything works locally - you realize that you need another PC on the same local network to do the waking (if the local network is not otherwise set up to let wake-on-lan packets through).

And just as you thought the scope of remote management has been solved, the remote PC stops crashing - and instead, it starts freezing; as it is impossible to turn it off remotely, the only thing the PC can do is run at 100% processor utilization, and turn itself off eventually, after some hours due to overheating or other scary stuff :) ''

That is why I was searching, for some time, for a cheap and accessible "waker" platform, that can:

  • Be accessible from a local network (assumming ssh access takes care of accessing the local network from the Internet)
  • Can forcibly turn off power to frozen computers
  • Can generate and send wake-on-lan packets
  • Will be constantly on (automatically on whenever power is present), and will not spend too much power

 

Concept & Usage

ArduinoWaker is an attempt to answer this search for "waker" platform, by using an Arduino with a W5100 Ethernet Shield, that uses a modified Sdfrethsh shell with added wake-on-lan capabilites. To allow for forcible turn-off, off-the-shelf USB-controlled power strip (extension lead) is used; as most of those devices only "sense" the presence of +5V on the USB bus, we can instead use a dedicated digital output from the Arduino, to allow for remote control of the power strip. A typical setup is shown on the figure below:

ArduinoWaker diagram
ArduinoWaker diagram (uses Fritzing and OpenClipArt graphics)

A typical scenario would be - upon working with the target PC remotely (say via VNC) it freezes; then we can log in to the local network via ssh, and from there

  • telnet into the Arduino
  • Issue a command to turn off power to target PC
  • Wait, then issue a command to turn on power to target PC
  • Wait, and finally issue a wake-on-lan packet to reboot the target PC

  Below is an example session demonstrating the above steps:

 $ ssh mysshserver.com
user@mysshserver.com's password:
...

[user@mysshserver.com ~]$ telnet 192.168.1.123
Trying 192.168.1.123...
Connected to 192.168.1.123.
Escape character is '^]'.
^]

telnet> mode character
^
Echo: ON
ardwakesh # ifconfig
DHCP_GKfig
1
mac address: de:ad:be:ef:fe:ed
ip address: 192.168.1.123
subnet mask: 255.255.255.0
gateway ip: 192.168.1.1
dhcp server ip: 0.0.0.0
dns server ip: 192.168.1.1


		Powerpins: [3]= 1;
ardwakesh # write 0 3
Writen to Pin 3: 0

		Powerpins: [3]= 0;
ardwakesh # write 1 3
Writen to Pin 3: 1

		Powerpins: [3]= 1;
ardwakesh # wmac AA:AA:AA:BB:BB:BB
 mac_wol/6: change OK:47
aa:aa:aa:bb:bb:bb

		Powerpins: [3]= 1;
ardwakesh # wip
 ip_wol/-1: 255.255.255.255

		Powerpins: [3]= 1;
ardwakesh # wport
 port_wol/-1: 7

		Powerpins: [3]= 1;
ardwakesh # wolex
wakeonlan -i 255.255.255.255 -p 7 aa:aa:aa:bb:bb:bb

Execute wakeonlan:
got socket 3
written: 102 ;  all sent.

		Powerpins: [3]= 1;
ardwakesh # ^]
telnet> q
Connection closed.

In the example session, it is pin 3 which controls the usb-controlled power strip (like on the ArduinoWaker diagram above). It is declared in code as a 'special' "powerpin", for whom the code ensures they are set to high voltage at startup (so the extension lead is powered, whenever ArduinoWaker receives power).

  • With "write 0 3" we turn off power to the extension lead (and thus the PC); and then
  • With "write 1 3" we turn power back on to the extension lead (and thus the PC)

The wake on lan functionality is, pretty much, copied from the wakeonlan script (found in Linux distros). As the shell currently has no backspace functionality (i.e. you cannot delete a character with backspace - backspace cancels the entire entry), entering a full wakeonlan command may be prone to errors. The code assumes that it will mostly work with one target PC, and hence it remembers its parameters (mac address, destination ip address and destination port) as global variables. There are correspondingly three commands: wmac, wip, and wport - which without arguments, print out the values of the respective global vars. With an argument, they attempt to parse the entered string and change the respective global variable.

Once you are sure that the target wake-on-lan parameters are OK by calling wmac, wip, and wport, you can then call wolex which will execute the actual wake-on-lan command (that is, it will create the wake-on-lan magic UDP packet and send it).

 

'Guaranteeing' a 'living' Ethernet shield at boot

One of the frustrations that can be met during Arduino Ethernet Shield development, is the problem that the ethernet shield will not automatically boot when Arduino is first powered; only after a hardware reset (caused either by pressing the button, or by programming the Arduino via USB (Arduino Forum - disable auto-reset by serial connection)) does the ethernet shield "wake up", and start running properly. (see also RFID Ethernet Shield Client Rails, Wiznet W5100 not running on 100M connection :: AVR Freaks)

Then one starts thinking about resetting the Arduino during the setup process; unfortunately, there is no such command that will reset hardware as well. There are possibilities to say use a watchdog, which requires changes in the Arduino bootloader (Wiblocks --- ATmega Software Reset, Arduino Forum - Reset arduino with code), but that one does not wake the shield either.

As one can easily demonstrate that the shield wakes up after powerup, if the RESET pin is briefly brought to ground; that may imply that a hardware hack is necesarry. Instead of going towards finding a dedicated one-shot (that could hold and propagate an RESET signal from a digital out pin); here something simpler is attempted (also mentioned as Atmel approach here) - that is, an RC circuit is established, where the capacitor begins charging on powerup. The voltage of the capacitor is brought to RESET - and thus, RESET will be held low for a while (and so, the board will be reset) during start of powerup, until the capacitor gets charged fully charged.

ArduinoWaker RC delay
ArduinoWaker RC delay

Using values of R=9.5KΩ and C=47uF, we get RC=0.4465s, and 5RC will be around 2 seconds - this "delayed RESET" seems to now allow the Ethernet shield to start immediately at power up, and to run the DHCP process.

Caveat - while Vc is connected to RESET, note that you cannot program the Arduino via USB; if you need to program the Arduino, simply remove the wire from the RESET pin.

 

Security

Obviously, this kind of setup gives yer Arduino a mega-super-user power: power to shut down and turn on a computer, even without an administrative password :) That, and given that the access is unencrypted through telnet, without any authentication whatsoever, should alert anyone wanting to try this in an organisational context. In that case, it is probably best you try to organise your own security (maybe restricting access to ArduinoWaker only from certain IP addresses, or through a script, etc).

 

Code

ArduinoWaker.pde:

 
/*
 *  ArduinoWaker.pde
 *  Shell-like environment for Arduino,
 *  with wake-on-lan facility.
 *  Based on sdfrethsh (https://playground.arduino.cc/Main/Sdfrethsh)
 *
 *
 *  For sim, build in serial mode, and:
 *  stty -icanon 115200 ; ./emulino /path/to/sdfruiteth.cpp.hex
 *  in order to get sim of tab, del and echo keypresses
 *
 *  ArduinoWaker.pde
 *  ------------
 *  Latest update: May 16 2010
 *  ------------
 *  Copyleft: use as you like
 *  sd [] imi.aau.dk
 *
 * Note: ping the device before you telnet to it, so the
 * Ethernet chip can wake up.
 *
 * Also, once in shell, do at least wip, wmac, wport once,
 * before executing wolex (to make sure packet gets sent,
 * it can be missed sometimes; repetitions should work though)
 *
 * an RC delayed reset may be necesarry for
 * Duemilanove + Ethernet Shield (W5100) , in order to guarantee
 * shield will be inited at power up
 */


// Commands

byte shellstate = 3; //start from show prompt state
/*
state = 0 : prompt has been shown, no in data yet
state = 1 : first incoming character came in,  data still incoming
state = 2 : EOL has been reach, incoming data completed
state = 3 : data has been processed, ready to show prompt.
*/
int timestep=0;
#define MAXCHARS 100
char line[MAXCHARS];
int linept=0;
char rch;
#define LF 10 //LineFeed
#define CR 13 //CarrRet
#define TAB 9
#define DEL 127
#define ECHR '^' //echo char
byte echomode=0;

// from minifruit shell - commands
#define READ 1
#define WRITE 2
#define OUT 3
#define IN 4
#define DELAY 5
#define PULSE 6
#define EXIT 7
#define VERSION 8
#define IFCFG 9
#define WMAC 10
#define WIP 11
#define WPORT 12
#define WOLEX 13

#define _MYNAME "Arduino"
#define _PROMPT "ardwakesh"
#define _HOSTNAME ""_MYNAME"-"_PROMPT //concatenate via defines..
static const char* PROMPT=&_PROMPT[0];
static const char* HOSTNAME=&_HOSTNAME[0];

static const char* CHGOK="change OK";

/*
* COMM FUNCTIONS  ****************************************************************
*/

// keep ETHERNET commented (undefined) for USB/serial mode build
#define ETHERNET

/*
* in ETHERNET case, the shell should be
* Server class - listening for
* incoming connections
*/

/*
* Note for ethernet:
* calling as:
*
*   stty -icanon ; telnet 192.168.1.77 23
*
* once connected, escape the telnet with ^] (Ctrl+]) and to into character mode:
*
*   ^]
*   telnet> mode character
*
* press enter - no message will be printed, but one is now in character mode.
* Then press Tab to show the help screen of the shell.
* No characters will be echoed, so you may want activate echo mode;
*   unfortunately '^' may get garbled by telnet, but you can copypaste it from
*   gnome-terminal from the help text shown on tab...
*
*/


// network configuration.  gateway and subnet are optional.
// Ethernet shield should be pingable at the address specified below,
//   its leds should blink at ping too
// start setting to static IP's - will be overwritten by DHCP
// these are settings related to "this" Arduino:
byte mac_ard[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
byte ip_ard[] = { 192, 168, 1, 123 };
byte gateway_ard[] = { 192, 168, 1, 1 };
byte subnet_ard[] = { 255, 255, 255, 0 };
byte ip_dhcp_srv[] = { 0, 0, 0, 0 };
byte ip_dns_srv[] = { 0, 0, 0, 0 };

// these are settings related to the target PC to be woken up:
byte mac_wol[] = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05 };
byte ip_wol[] = { 255, 255, 255, 255 };
int port_wol = 7;
//local port to "listen" on - to initialize udp, else we dont use it
// shows as udp src port in wireshark
int port_udploc_wol = 8888;

byte wol_magic_packet[102] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };

boolean ipAcquired = false;

// cannot just include these - must be extern
extern "C" {
   #include "../Ethernet/utility/types.h" //uint8...
   #include "../Ethernet/utility/socket.h" //socket
   #include "../Ethernet/utility/w5100.h" //Sn_MR_UDP
}

// powerpins - those digital outs designated to
// be connected to a power rail.
// we must ensure powerpins will be high voltage at boot!
// "Arduino uses digital pins 10, 11, 12, and 13 (SPI)
// to communicate with the W5100 on the ethernet shield.
// These pins cannot be used for general i/o. "
// we better leave 1 and 2 as well, since those could
// be used for usb serial.
byte powerpins[] = { 3 };
byte powerpinssize = sizeof(powerpins) / sizeof(byte);
// LED connected to digital pin 13 on Duemilanove
int ledPin = 13;


#ifdef ETHERNET
  static byte commmode = 1; // ethernet
  /*
  choice of dhcp library - for more info on install etc, see:
  https://sdaaubckp.svn.sourceforge.net/viewvc/sdaaubckp/sdfrethsh/ardtestdhcp.pde
  choose only one define - comment the rest :)
  if none are chosen, we should revert to static IP setup!!
  */
  //#define DHCP_JT // jordanterrell - Arduino-DHCPv0.4
  //#define DHCP_KG // kegger - (A)Ethernet
#define DHCP_GK // gkaindl - ArduinoEthernet/EthernetDHCP
  // but also must comment the includes too -
#if defined(DHCP_JT)
  //static char* dhcplib="DHCP_JT";
  //#include <Ethernet.h> //jt-WebClientWithDHCP
  //#include <jt_Dhcp.h> //jt-WebClientWithDHCP
#elif defined(DHCP_KG) //DHCP_JT
  //static char* dhcplib="DHCP_KG";
  //#include <AEthernet.h> //kegger-WebClientWithDHCP
  //#include "Dhcp.h"  //kegger-WebClientWithDHCP - this now specifically should refer to kegger version
#elif defined(DHCP_GK) //DHCP_KG
  static char* dhcplib="DHCP_GK";
  #include <Ethernet.h> //gkeindl: PollingDHCP.pde
  #include <EthernetDHCP.h> //gkeindl: PollingDHCP.pde
#elif // no DHCP, so static..
  static char* dhcplib="NO DHCP";
  ipAcquired = true;
#endif //DHCP_...JT
#else // #if(n)def ETHERNET
  #include <Ethernet.h> // including it here, so it don't crash on 'Server server'
  static char* dhcplib="NO ETH";
  static byte commmode = 0; // serial
#endif // ETHERNET


// telnet defaults to port 23
Server server = Server(23);


void commBegin()
{
#ifdef ETHERNET
  delay(1000); //does it help? .. yes, for registering first DHCP request
  setupDHCP(); // init of Ethernet and DHCP
  // start listening for clients
  server.begin();
#else
  Serial.begin(115200);
#endif
}


int commAvailable()
{
#ifdef ETHERNET
  return server.available();
#else
  return Serial.available();
#endif
}



byte commRead()
{
#ifdef ETHERNET
  //the client read seems to block until enter is received
  // use telnet's character mode to get char by char response
  Client tclient = server.available();
  return tclient.read();
#else
  // serial will block in emulation until enter is received, unless
  // stty -icanon is ran before emulating..
  return Serial.read();
#endif
}

// Variadic macros are C99-only
#ifdef ETHERNET
#define commPrint(...)  do { server.print(__VA_ARGS__); } while (0)
#define commPrintln(...)  do { server.println(__VA_ARGS__); } while (0)
#else
#define commPrint(...)  do { Serial.print(__VA_ARGS__); } while (0)
#define commPrintln(...)  do { Serial.println(__VA_ARGS__); } while (0)
#endif


/*
* COM FUNCTIONS - DHCP  **********************************************************
*/

#ifdef ETHERNET
void setupDHCP()
{
#if defined(DHCP_JT)
  jt_dhcp_setup();
#elif defined(DHCP_KG)
  kg_dhcp_setup();
#elif defined(DHCP_GK)
  gk_dhcp_setup();
#elif // no DHCP defines - so, static IP setup:
  Ethernet.begin(mac_ard, ip_ard, gateway_ard, subnet_ard);
#endif
}

#ifdef DHCP_JT
// from jt-Arduino-DHCPv0.4/examples/WebClientWithDHCP/WebClientWithDHCP.pde
void jt_dhcp_setup()
{

  commPrintln("getting ip...");
  //int result = Dhcp.beginWithDHCP(mac_ard);
  // 10 s wait time for DHCP offer - else it don't work for me
  int result = Dhcp.beginWithDHCP(mac_ard, 60000, 10000);

  if(result == 1)
  {
    ipAcquired = true;

    commPrintln("ip acquired...");

    // get data, write
    Dhcp.getLocalIp(ip_ard);
    Dhcp.getSubnetMask(subnet_ard);
    Dhcp.getGatewayIp(gateway_ard);
    Dhcp.getDhcpServerIp(ip_dhcp_srv);
    Dhcp.getDnsServerIp(ip_dns_srv);

    ifconfig();

    delay(3000);
  }
  else
    commPrintln("unable to acquire ip address...");
}
#endif //DHCP_JT

#ifdef DHCP_KG
// from kegger_Ethernet/examples/WebClientWithDHCP/WebClientWithDHCP.pde
void kg_dhcp_setup()
{
  commPrintln("getting ip...");
  int result = Dhcp.beginWithDHCP(mac_ard);

  if(result == 1)
  {
    ipAcquired = true;

    commPrintln("ip acquired...");

    // get data, write
    Dhcp.getLocalIp(ip_ard);
    Dhcp.getSubnetMask(subnet_ard);
    Dhcp.getGatewayIp(gateway_ard);
    Dhcp.getDhcpServerIp(ip_dhcp_srv);
    Dhcp.getDnsServerIp(ip_dns_srv);

    ifconfig();

    delay(3000);
  }
  else
    commPrintln("unable to acquire ip address...");
}
#endif //DHCP_KG

#ifdef DHCP_GK
// from gkaindl_EthernetDHCP/examples/PollingDHCP/PollingDHCP.pde
void gk_dhcp_setup()
{
  // Initiate a DHCP session. The argument is the MAC (hardware) address that
  // you want your Ethernet shield to use. The second argument enables polling
  // mode, which means that this call will not block like in the
  // SynchronousDHCP example, but will return immediately.
  // Within your loop(), you can then poll the DHCP library for its status,
  // finding out its state, so that you can tell when a lease has been
  // obtained. You can even find out when the library is in the process of
  // renewing your lease.
  EthernetDHCP.setHostName(_HOSTNAME);
  EthernetDHCP.begin(mac_ard, 1);
}

void gk_poll_loop_dhcp()
{
  static DhcpState prevState = DhcpStateNone;
  static unsigned long prevTime = 0;

  // poll() queries the DHCP library for its current state (all possible values
  // are shown in the switch statement below). This way, you can find out if a
  // lease has been obtained or is in the process of being renewed, without
  // blocking your sketch. Therefore, you could display an error message or
  // something if a lease cannot be obtained within reasonable time.
  // Also, poll() will actually run the DHCP module, just like maintain(), so
  // you should call either of these two methods at least once within your
  // loop() section, or you risk losing your DHCP lease when it expires!
  DhcpState state = EthernetDHCP.poll();

  if (prevState != state) {
    commPrintln();

    switch (state) {
      case DhcpStateDiscovering:
        commPrint("Discovering servers.");
        break;
      case DhcpStateRequesting:
        commPrint("Requesting lease.");
        break;
      case DhcpStateRenewing:
        commPrint("Renewing lease.");
        break;
      case DhcpStateLeased: {
        commPrintln("Obtained lease!");

        // added:
        ipAcquired = true;

        // Since we're here, it means that we now have a DHCP lease, so we
        // save some information.
        memcpy(&ip_ard, EthernetDHCP.ipAddress(), 4);
        memcpy(&gateway_ard, EthernetDHCP.gatewayIpAddress(), 4);
        memcpy(&ip_dns_srv, EthernetDHCP.dnsIpAddress(), 4);

        commPrintln();

        break;
      }
    }
  } else if (state != DhcpStateLeased && millis() - prevTime > 300) {
     prevTime = millis();
     commPrint('.');
  }

  prevState = state;

}
#endif //DHCP_GK
#endif //ETHERNET


/*
* MAIN FUNCTIONS  ****************************************************************
*/

void setup()
{
  // initialize powerpins to high voltage level immediately!
  for (int ix=0; ix<powerpinssize; ix++)
  {
    pinMode(powerpins[ix], OUTPUT);
    digitalWrite(powerpins[ix], HIGH);
  }

  commBegin(); // initialize the communication
  // the below call causes total freeze in setup!
  //socket(UDPSOCK,Sn_MR_UDP,port_udploc_wol,0);
}

void loop()
{
#ifdef ETHERNET
if (!ipAcquired) { // ok for static, should be true..
#if defined(DHCP_GK) //cannot call setupDHCP for poll, so:
     gk_poll_loop_dhcp();
#else //not DHCP_GK
    setupDHCP();
#endif //DHCP_GK
  } // end if
#endif //ETHERNET
  if (shellstate == 3) {
    printPrompt();
    shellstate = 0;
  }
  checkForInData();
  processInData();
  //commPrintln(shellstate);
  timestep++;
#ifdef DHCP_GK
  // this called maybe each cca 20s?
  if (timestep%100 == 0) EthernetDHCP.maintain(); //poll is called only during setup!;
#endif
  delay(20);
}






/*
* SHELL FUNCTIONS  ****************************************************************
*/

void printPrompt()
{
  commPrint(PROMPT);
  commPrint(" # ");
}

void printPowerpins()
{
  commPrint("Powerpins: ");
  for (int ix=0; ix<powerpinssize; ix++)
  {
    commPrint("[");
    commPrint(powerpins[ix], DEC);
    commPrint("]= ");
    commPrint(digitalRead(powerpins[ix]), DEC);
    commPrint("; ");
  }
}

void checkForInData()
{
  while(commAvailable()) // does not block if no data available
  {
    rch = commRead();
    line[linept] = rch;
    linept++;

    if (rch == TAB){
      // usage and reset - for tab
      printUsage();
      shellstate = 3;
      linept = 0;
      return;
    }

    if (rch == DEL){
      // immediate reset - for delete
      commPrintln();
      shellstate = 3;
      linept = 0;
      return;
    }

    if (rch == ECHR){
      // switch echo mode and reset
      commPrintln();
      commPrint("Echo: ");
      if (echomode == 0) {
        echomode = 1;
        commPrintln("ON");
      } else {
        echomode = 0;
        commPrintln("off");
      }
      shellstate = 3;
      linept = 0;
      return;
    }

    if (echomode == 1) commPrint(rch);

    if (shellstate == 0) {
      shellstate = 1;
      //commPrintln();
      //commPrintln("checkForInData ");
    }

    line[linept] = 0;
    if ((rch == CR) || (rch == LF))
    {
      shellstate = 2;
    }
  }
}


void processInData()
{
  if (shellstate == 2)
  {
    if (echomode == 1) commPrintln(); //add newline for echo mode
    linept--; //ignore last EOL
    line[linept] = 0; // and shorten string
    // printout command
    commPrint("> ");
    commPrint(line);


    // parse'n'execute command
    execCommand();

    // add empty line
    commPrintln();

    // printout state of powerpins
    commPrint("\t\t");
    printPowerpins();
    commPrintln();

    shellstate = 3;
    linept = 0;
  }
}




// orig: showConsole() in minifruit shell
void execCommand()
{
   //Do command
   int command=parseLine(line);
   int param1,param2,param3;
   int ret;

   switch(command)
   {
   case READ :
       // Parse param as pin number
       param1 = line[5] - '0';
       if (line[6]>='0' && line[6]<='9')
         param1=10*param1+line[6]-'0';

       commPrint("Pin ");
       commPrint(param1);
       commPrint(": ");
       commPrintln(digitalRead(param1));
       break;

   case WRITE  :
     param1 = line[6] - '0'; // Digital value
     param2 = line[8] - '0'; // Line number
       if (line[9]>='0' && line[9]<='9')
         param2=10*param2+line[9]-'0';
       digitalWrite(param2,param1);
       commPrint("Writen to Pin ");
       commPrint(param2);
       commPrint(": ");
       commPrintln(param1);

     break;

    case OUT:
         param1 = line[7] - '0';
         if (line[8]>='0' && line[8]<='9')
         param1=10*param1+line[8]-'0';
         pinMode(param1, OUTPUT);
         commPrint("Output Pin ");
         commPrintln(param1);
    break;

    case IN:
         param1 = line[6] - '0';
         if (line[7]>='0' && line[7]<='9')
         param1=10*param1+line[7]-'0';
         pinMode(param1, OUTPUT);
         commPrint("Input Pin ");
         commPrint(param1);
         break;
     case DELAY:
         param1 = line[6] - '0'; // Digital value
         param2 = line[8] - '0';
         param3 = line[10] - '0'; // Line number
         if (line[11]>='0' && line[11]<='9')
         param3=10*param3+line[11]-'0';
         commPrint("Active pin ");
         commPrint(param3);
         commPrint(" by ");
         commPrint(param1);
         commPrint(" seconds value:");
         commPrintln(param2);
         digitalWrite(param3,param2);
         delay(1000*param1);
         digitalWrite(param3,!param2); // Not of parameter
     break;
     case PULSE:
         param1 = line[6] - '0'; // Voltage Level
         param2 = line[8] - '0'; // Line Number
         if (line[11]>='0' && line[11]<='9')
         param2=10*param2+line[11]-'0';

         commPrint("Wave to pin ");
         commPrint(param2);
         commPrint(" by ");
         commPrint(param1);
         commPrintln(" V");
         analogWrite(param2,param1*50);

       break;
     case VERSION: commPrintln("Version 1.0.0"); break;
     case IFCFG: ifconfig(); break;
     case WMAC:
         commPrint(" mac_wol/");
         // %hhx - read and store hex as byte!
         // else corruption of next variable (ip_wol)!
         ret = sscanf (&line[5], "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",
           &mac_wol[0], &mac_wol[1], &mac_wol[2],
           &mac_wol[3], &mac_wol[4], &mac_wol[5] );
         commPrint(ret, DEC); commPrint(": ");
         if (ret>0) commPrintln(CHGOK);
         printArrayln(":", mac_wol, 6, 16);
         break;
     case WIP:
         commPrint(" ip_wol/");
         // %hhd - read and store decimal as byte!
         // else corruption of next variable (port_wol)!
         ret = sscanf (&line[4], "%hhd.%hhd.%hhd.%hhd",
           &ip_wol[0], &ip_wol[1], &ip_wol[2],
           &ip_wol[3] );
         commPrint(ret, DEC); commPrint(": ");
         if (ret>0) commPrintln(CHGOK);
         printArrayln(".", ip_wol, 4, 10);
         break;
     case WPORT: commPrint(" port_wol/");
         ret = sscanf (&line[6], "%d",
           &port_wol);
         commPrint(ret, DEC); commPrint(": ");
         if (ret>0) commPrintln(CHGOK);
         commPrintln(port_wol);
         break;
     case WOLEX:
         wakeonlan();
         break;
     case EXIT: if ((echomode == 0) && (commmode ==0)) exit(0); break; // only useful for sim!!
     default: commPrintln("Unknown command"); break;
   }

}

void wakeonlan()
{
  int ret;
  //sprintf(cmd, "wakeonlan -i %d.%d.%d.%d -p %d %0x:%0x:%0x:%0x:%0x:%0x");
  commPrint("wakeonlan -i ");
  printArray(".", ip_wol, 4, 10);
  commPrint(" -p ");
  commPrint(port_wol);
  commPrint(" ");
  printArrayln(":", mac_wol, 6, 16);

  // compose packet wol_magic_packet
  for (int ix=6; ix<102; ix++)
  {
    wol_magic_packet[ix]=mac_wol[ix%6];
  }

  commPrintln();


#ifdef ETHERNET
  commPrintln("Execute wakeonlan: ");
  ret = UDP_RawSendto(wol_magic_packet, 102, ip_wol, port_wol);

  commPrint("written: ");
  commPrint(ret, DEC);
  commPrint(" ; ");
  if (ret == 102) commPrint(" all sent. ");
  commPrintln();

#else // if(n)def ETHERNET
  printArrayln(":", wol_magic_packet, 102, 16);
  commPrintln(dhcplib);
#endif
}


int UDP_RawSendto(byte* in_packet, int in_len, byte* in_ip, int in_port)
{
  int ret;
  int _socket;

  // we must obtain a free socket (one not taken by the server,
  //  which should be socket 0)
  // and then we must close it at end!

  for (int i = 3; i>=0; i--) {
  //commPrintln(i, DEC);
  if (SOCK_CLOSED == IINCHIP_READ(Sn_SR(i))) {
     //commPrintln("sock_closed");
     if (socket(i, Sn_MR_UDP, port_udploc_wol, 0) > 0) {
        commPrint("got socket ");
        commPrintln(i, DEC);
        _socket = i; //this->_socket = i;
        break;
     }
  }
  }

  ret = sendto(_socket,(uint8*)in_packet,in_len,(uint8*)in_ip,in_port);

  close(_socket);

  return ret;
}


void printUsage()
{

commPrintln("Console Usage:");
commPrint("        ");
commPrint(ECHR);
commPrintln("                   : Switch echo mode ");
commPrintln("        read <pin>          : Read target pin ");
commPrintln("	write <value> <pin> : Write value to desired pin ");
commPrintln("	output <pin> 	    : Configure pin as output ");
commPrintln("	input  <pin>		: Configure pin as input ");
commPrintln("	delay <second> <value> <pin> : Writes value to pin for given delay ");
commPrintln("	pulse <value> <pin>	: Arrages voltage value to given pin by PWM ");
commPrintln("        exit				: Exit");
commPrintln("        hello				: Version");
commPrintln("        ifconfig				: show IP setup ");
commPrintln("        wmac			: show/edit WOL MAC addr ");
commPrintln("        wip			: show/edit WOL IP addr ");
commPrintln("        wport			: show/edit WOL port ");
commPrintln("        wolex			: execute WOL ");
}


int stringCompare(char* line1,char* line2,int length)
/*Returns 1 when they are equal*/
{
  int i=0;
  int result=1;
  for(i=0;i<length;i++)
     result = result && (line1[i]==line2[i]);
  return result;
}

int stringLength(char* line)
{
  int i;
  for(i=0;line[i]!=0;i++);
  return i;
}


int parseLine(char* line)
{
  //if (stringCompare(line,"exit",4) || (stringLength(line) < 4 )) return EXIT;
  if (stringCompare(line,"exit",4)) return EXIT;
  if (stringCompare(line,"read",4)) return READ;
  if (stringCompare(line,"write",5)) return WRITE;
  if (stringCompare(line,"output",5)) return OUT;
  if (stringCompare(line,"input",5)) return IN;
  if (stringCompare(line,"delay",5)) return DELAY;
  if (stringCompare(line,"pulse",5)) return PULSE;
  if (stringCompare(line,"hello",5)) return VERSION;
  if (stringCompare(line,"ifconfig",8)) return IFCFG;
  if (stringCompare(line,"wmac",4)) return WMAC;
  if (stringCompare(line,"wip",3)) return WIP;
  if (stringCompare(line,"wport",5)) return WPORT;
  if (stringCompare(line,"wolex",3)) return WOLEX;
}


//jt-WebClientWithDHCP
//void printArray(Print *output, char* delimeter, byte* data, int len, int base)
void printArray(char* delimeter, byte* data, int len, int base)
{
  char buf[10] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0};

  for(int i = 0; i < len; i++)
  {
    if(i != 0)
      commPrint(delimeter); //output->print(delimeter);

    commPrint(itoa(data[i], buf, base)); //output->print(itoa(data[i], buf, base));
  }

}

void printArrayln(char* delimeter, byte* data, int len, int base)
{
  printArray(delimeter, data, len, base);
  commPrintln(); //output->println();
}

// ifconfig - print out address info, lol :) .. (//jt-WebClientWithDHCP)
void ifconfig()
{
  byte buffer[6];

  commPrintln(dhcplib);
  commPrintln(ipAcquired, DEC);

  commPrint("mac address: ");
  printArrayln(":", mac_ard, 6, 16);

  commPrint("ip address: ");
  printArrayln(".", ip_ard, 4, 10);

  commPrint("subnet mask: ");
  printArrayln(".", subnet_ard, 4, 10);

  commPrint("gateway ip: ");
  printArrayln(".", gateway_ard, 4, 10);

  commPrint("dhcp server ip: ");
  printArrayln(".", ip_dhcp_srv, 4, 10);

  commPrint("dns server ip: ");
  printArrayln(".", ip_dns_srv, 4, 10);

  commPrintln();
}


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