SparkFun Forums 

Where electronics enthusiasts find answers.

All things pertaining to wireless and RF links
By Valen
The hex value CF (or any part of a word containing it for that matter) does not occur in the product manual. So I think this is a matter for Support to answer what this status answer might be (of ATAI). Undocumented it seems.

Manual: ... 2180_K.pdf

Module product page: ... wi-fi#docs

p.s. Or better, try to manually perform the same commands that the code does via a terminal program (XCTU) to connect with the AP and see if you get the same response. There is some byte-juggling going on in the code with the status values. So better make sure that isn't distorting things.
By phamilton
Hi Valen, Thanks for your reply!! I went through the documentation you provide and could not find any hints to the issue I am having...

Odd thing is that when I use XCTU i can connect perfectly to my network...

Ill keep grinding away!

By starkforce

Any luck with your problem?

I am having the same issue. Xbee works and connects just fine with XTCU but keep getting "Waiting to connect: CF" from the serial.

By phamilton
Yes! after MANY hours I finally got it to work!! The Sparkfun (SF) instructions for the bee wifi for some reason are incomplete... I went to GITHUB and got some code there... Problem was they were not too clear on how to set up XCTU... This is the code I used to FINALLY get the XBEE WIFI to connect and send data to SF Data...

I modified the code slightly..

You will notice it is similar to the SF code... I did not bother to compare to see the differences...

BTW make sure your SF shield is set to DLINE

my hardware:
Arduino UNO
SF xbee shield
xbee wifi module
xbee usb explorer - bought off eBay

Code: Select all
///////////////////    START     //////////////////////////////////////////////////////////////////////
/* ***************************************************************
Post data to SparkFun's data stream server system (phant) using
an XBee WiFi and XBee Shield.

This sketch uses an XBee WiFi and an XBee Shield to get on
the internet and POST analogRead values to SparkFun's data
logging streams (

Hardware Hookup:
  The Arduino shield makes all of the connections you'll need
  between Arduino and XBee WiFi. If you have the shield make
  UART   uses pins D0 and D1
  DLINE  uses pins D2 and D3 default 
  USE DLINE and spark fun xbee shield

Requires the lovely Phant library:

Development environment specifics:
    IDE: Arduino 1.0.5
    Hardware Platform: SparkFun RedBoard

my SF plant stuff
Public Key: xxx
Private Key: yyy
Delete Key: zzz

Stream URL:

If you need help getting started, visit for more info.

#include <SoftwareSerial.h>
#include <Phant.h>

// Time in ms, where we stop waiting for serial data to come in
// 2s is usually pretty good. Don't go under 1000ms (entering
// command mode takes about 1s).
#define COMMAND_TIMEOUT 3000         // ms

// Phant Stuff
String destIP = "";     //'s IP address
String publicKey = "xxx";
String privateKey = "yyy";
Phant phant("", publicKey, privateKey);
const String FieldOne = "var1";
const String FieldTwo = "var2";

// XBee Stuff, we create a synthetic serial connection since the Arduino UNO only has one
const byte XB_RX = 2;                // XBee's RX (Din) pin
const byte XB_TX = 3;                // XBee's TX (Dout) pin
const int  XBEE_BAUD = 9600;         // Your XBee's baud (9600 is default)
SoftwareSerial xB(XB_RX, XB_TX); 

// variables used
float valueOne     = 0;
float valueTwo     = 0;

// Phant limits you to 10 seconds between posts. Use this variable
// to limit the update rate (in milliseconds):
const unsigned long UPDATE_RATE = 15000;
unsigned long lastUpdate        = 0;            // Keep track of last update time

bool sendError = false;

// *****************************************************************************************************
// ****  SETUP     *************************************************************************************
// *****************************************************************************************************
void setup()
  // We have a 5 second delay to give the shield and XBee module some 
  // time to settle down. Without this things weren't starting up
  // properly unless the reset button was hit after power up.
  // Set up serial ports:

  // Set up WiFi network
  Serial.println("Testing network");
  Serial.print("IP Address: "); printIP(); Serial.println("......");

  // setupHTTP() will set up the destination address, port, and
  // make sure we're in TCP mode:

// *****************************************************************************************************
// ****  MAIN LOOP     *********************************************************************************
// *****************************************************************************************************
void loop()
  // If current time is UPDATE_RATE milliseconds greater than
  // the last update rate, send new data.
  if (millis() > (lastUpdate + UPDATE_RATE)) {
    Serial.print("\nSending update...");
    if (sendData())  {
      sendError = false;
      Serial.println(" SUCCESS!");
    } else {
      sendError = true; 
      Serial.println(" Failed :(");
    lastUpdate = millis();
  //Serial.print(FieldOne); Serial.print(" - "); Serial.println(valueTwo);
  //Serial.print(FieldTwo); Serial.print(" - "); Serial.println(valueOne);

// *****************************************************************************************************
// ****  FUNCTIONS     *********************************************************************************
// *****************************************************************************************************
// sendData() makes use of the PHANT LIBRARY to send data to the
// server. We'll use phant.add() to add specific
// parameter and their values to the param list. Then use
// to send that data up to the server.
int sendData()
  xB.flush();                           // Flush data so we get fresh stuff in
  readSensors();                        // Get updated values from sensors.
  phant.add(FieldOne, valueOne);
  phant.add(FieldTwo, valueTwo);
  // After our PHANT.ADD's we need to PHANT.POST(). The post needs
  // to be sent out the XBee. A simple "print" of that post will
  // take care of it.

  // Check the response to make sure we receive a "200 OK". If 
  // we were good little programmers we'd check the content of
  // the OK response. If we were good little programmers...
  char response[12];
  if (waitForAvailable(12) > 0) {
    for (int i=0; i<12; i++) {
      response[i] =;
    if (memcmp(response, "HTTP/1.1 200", 12) == 0)
      return 1;
    else {
      Serial.print("Server repsonse ---- ");
      return 0; // Non-200 response
  else // Otherwise timeout, no response from server
    return -1;

void readSensors()
  valueTwo = random (0,50);
  valueOne = random (0,50);

// XBee WiFi Setup Stuff //
// setupHTTP() sets three important parameters on the XBee:
// 1. Destination IP -- This is the IP address of the server we want to send data to.
// 2. Destination Port -- We'll be sending data over port 80. The standard HTTP port a server listens to.
// 3. IP protocol -- We'll be using TCP (instead of default UDP).

void setupHTTP(String address)
  // Enter command mode, wait till we get there.
  while (!commandMode(1))  ;

  // Set IP (1 - TCP)
  command("ATIP1", 2);                    // RESP: OK
  // Set DL (destination IP address)
  command("ATDL" + address, 2);           // RESP: OK
  // Set DE (0x50 - port 80)
  command("ATDE50", 2);                   // RESP: OK

  commandMode(0);                         // Exit command mode when done

// printIP() //
// Simple function that enters command mode, reads the IP and
// prints it to a serial terminal. Then exits command mode.
void printIP()
  // Wait till we get into command Mode.
  while (!commandMode(1))
  // Get rid of any data that may have already been in the
  // serial receive buffer:
  // Send the ATMY command. Should at least respond with "\r" (7 characters):
  command("ATMY", 7);
  // While there are characters to be read, read them and throw
  // them out to the serial monitor.
  while (xB.available() > 0)  {
  // Exit command mode:

// Assumes you've already configured your XBee module's WiFi settings using X-CTU
// and simply blinks the LED while connecting or if there is a problem. We also
// turn on the LED once connected.
void connectWiFi()
  const String CMD_SSID = "ATID";
  const String CMD_ENC = "ATEE";
  const String CMD_PSK = "ATPK";
  // Check if we're connected. If so, sweet! We're done.
  // Otherwise, time to configure some settings, and print
  // some status messages:
  int status;
  while ((status = checkConnect()) != 0)
    // Print a status message. If `status` isn't 0 (indicating
    // "connected"), then it'll be one of these 
    //  (from XBee WiFI user's manual):
    // 0x01 - WiFi transceiver initialization in progress. 
    // 0x02 - WiFi transceiver initialized, but not yet scanning 
    //        for access point. 
    // 0x13 - Disconnecting from access point. 
    // 0x23 – SSID not configured. 
    // 0x24 - Encryption key invalid (either NULL or invalid 
    //        length for WEP) 
    // 0x27 – SSID was found, but join failed. 0x40- Waiting for 
    //        WPA or WPA2 Authentication 
    // 0x41 – Module joined a network and is waiting for IP 
    //        configuration to complete, which usually means it is
    //        waiting for a DHCP provided address. 
    // 0x42 – Module is joined, IP is configured, and listening 
    //        sockets are being set up. 
    // 0xFF– Module is currently scanning for the configured SSID.
    // We added 0xFE to indicate connected but SSID doesn't match the provided id.
    Serial.print("Waiting to connect: ");
    Serial.println(status, HEX);

// Check if the XBee is connected to a WiFi network.
// This function will send the ATAI command to the XBee.
// That command will return with either a 0 (meaning connected)
// or various values indicating different levels of no-connect.
byte checkConnect()
  byte i=0xFF;
  char temp[2];
  while (!commandMode(1))
  command("ATAI", 2);
  temp[0] = hexToInt(;
  temp[1] = hexToInt(;
  #ifdef DEBUG
    Serial.print("temp[0] = ");   Serial.println(temp[0], HEX);
    Serial.print("temp[1] = ");   Serial.println(temp[1], HEX);
  #endif  //
  if (temp[0] == 0) {
    return 0;
  else {
    return (temp[0]<<4) | temp[1];

// Low-level, ugly, XBee Functions //
void command(String atcmd, int rsplen)
  #ifdef DEBUG
    Serial.print("Entering command: ");
  #ifdef DEBUG

int commandMode(boolean enter)
  if (enter)  {
      #ifdef DEBUG
         Serial.println("Entering Command Mode");
    char c;
    xB.print("+++");   // Send CMD mode string
    if (xB.available() > 0)  {
      c =;
      #ifdef DEBUG
        Serial.print("Command Mode Response: ");
      if (c == 'O')       // That's the letter 'O', assume 'K' is next
        return 1;         // IF we see "OK" return success
    return 0;             // If no (or incorrect) receive, return fail
  else  {
   #ifdef DEBUG
    Serial.println("Exiting Command Mode");
    command("ATCN", 2);
    return 1;

int waitForAvailable(int qty)
  int timeout = COMMAND_TIMEOUT;

  while ((timeout-- > 0) && (xB.available() < qty))

  return timeout;

byte hexToInt(char c)
  if (c >= 0x41) // If it's A-F
    return c - 0x37;
    return c - 0x30;

///////////////////    END     //////////////////////////////////////////////////////////////////////
I have the following settings In XCTU:

ID - ssid
EE - security mode
NS - DNS address
DE - 50 hex which is port 80 in decimal
GW, GW, MK, MY - the settings the router assigns

the rest are the default, out of the box settings...

Hope all this works for you!!
Last edited by phamilton on Sun May 17, 2015 6:54 pm, edited 1 time in total.
By Valen
Please write your code in between [ code] [/code ] blocks. (remove my spaces) Simply inserting it in the text makes it a huge page. There is also a button in the full editor to insert it in the message. Then simply copy/paste it in between.
By starkforce
Hi phamilton,

Sorry for the slow reply, I didn't realize you had responded.

I checked out your post and code. I tested it out myself and it works correctly. Thank you for sharing.

Prior to reading your respond, I had narrowed the issue down to the Xbee's DNS. For whatever reason, the settings were getting wiped out after I disconnected power to the Xbee. All the other changed settings (SSID, Password, etc.) saved but the DNS always reset. Still not sure why but I'll figure it out in time.

I do like Sparkfun however their guides do need some love.

Again, thank you for sharing.

By ricardo21
Hello everyone!

I'm having the same trouble that phamilton had. I can ping my S6B module but using the code he post, i can't send the post message to the sparkfun database :(
It returns -1 in the sendData() function and i can't figure it out why i happens.
Can you help me with the XCTU configuration? Is there any trick to make it work?

Best Regards,

By ls899

Your code is definitely doing a lot more than the one that Sparkfun posted.

Unfortunately, I keep getting an error:

Sending update...Server repsonse ---- HTTP/1.1 400
Failed :(

I tried to look through the code itself to see why this is happening, but I cannot seem to figure it out. Any help you could provide would be amazing, thank you!
By ke7kcb
The code and advice above was really helpful, especially programming many of the Xbee parameters via XCTU rather than by AT commands in the connectWifi() function. I also found that it is very important to add delay(1000) before and after the xB.print("xxx") line of code in the commandMode function. I think the code above managed to meet the guard times by accident rather than intention. See the XBee user manual Page 34 regarding AT command mode and guard times.


long long title how many chars? lets see 123 ok more? yes 60

We have created lots of YouTube videos just so you can achieve [...]

Another post test yes yes yes or no, maybe ni? :-/

The best flat phpBB theme around. Period. Fine craftmanship and [...]

Do you need a super MOD? Well here it is. chew on this

All you need is right here. Content tag, SEO, listing, Pizza and spaghetti [...]

Lasagna on me this time ok? I got plenty of cash

this should be fantastic. but what about links,images, bbcodes etc etc? [...]