I'm working on a project where I would like to send the output from the Advancer Technologies EMG sensor (from Sparkfun) to an Arduino Uno wirelessly. Since the output is analog and only going one direction, I think the Series 1 should be able to handle it.
My question is: is this feasible? Or will I need an Arduino to transmit the EMG Sensor output via XBee?
Thanks!
A link to the device in question is far better than a hand-waving description.
If the output IS analog, then an XBee can be configured to read the data and transmit it, without the need for an Arduino on that end.
Sorry, I couldn't paste while on mobile for some reason.
Here's a link to the sensor kit - MyoWare 2.0 Muscle Sensor - DEV-21265 - SparkFun Electronics
Thanks!
The Arduino example is crap, but it appears that the sensor(s) could be connected directly to analog pins on the XBee.
The XBee only has 4 analog pins, if that matters.
Thanks PaulS! I'll only need one input, so I should be fine.
Any chance you can point me in the right direction of how to read in the analog XBee input?
I think it should be the same as if the sensor is connected directly to the Arduino. If that's the case, could I use SoftwareSerial to read in the analog input from the XBee and output those values to the serial monitor?
Any chance you can point me in the right direction of how to read in the analog XBee input?
When you configure the XBee to measure analog or digital pins, you need to also configure it to use API (not AT) mode.
This makes the XBee send a fixed content packet that is easy to parse.
If you don't have Rob Faludi's book, Building Wireless Sensor Networks, get it.
PaulS:
When you configure the XBee to measure analog or digital pins, you need to also configure it to use API (not AT) mode.This makes the XBee send a fixed content packet that is easy to parse.
If you don't have Rob Faludi's book, Building Wireless Sensor Networks, get it.
I downloaded Rob Faludi's book and it definitely helped explain API packets. I have the two XBees talking with each other with one set to API=2 and one in AT with DI0 set to ADC (I successfully followed this tutorial to send AT commands from the API XBee to an LED on the AT XBee). As a basic example, I found some code sending values from a pot on a remote XBee to an arduino to control brightness of an LED.
The problem I'm running in to is I only get two values - 0 when the knob is turned all the way to one side, and 3.3 when I start turning it the opposite direction.
I don't think the code is the problem, but just in case:
#include <SoftwareSerial.h>
int const LEDPIN = 11;
SoftwareSerial XBee(2, 3);
void setup(){
// Start up our serial port, we configured our XBEE devices for 9600 bps.
Serial.begin(9600);
XBee.begin(9600);
pinMode(LEDPIN,OUTPUT);
// while the serial stream is not open, do nothing:
while (!Serial) ;
}
void loop(){
if (XBee.available() >= 20) { // Wait until we have a mouthful of data
if (XBee.read() == 126) { // Start delimiter of a frame
// Skip over the bytes in the API frame we don't care about
for (int i = 0; i < 10; i++) {
XBee.read();
}
// The next two bytes are the high and low bytes of the sensor reading
int analogHigh = XBee.read();
int analogLow = XBee.read();
float analogValue = (analogLow + (analogHigh * 256))*3.3/1023;
// Scale the brightness to the Arduino PWM range
int brightness = map(analogValue, 0, 1023, 0, 255);
// Light the LED
analogWrite(LEDPIN, brightness);
Serial.println(analogValue);
}
}
}
And I attached a picture of how I have things wired on the remote XBee (I'm using the SparkFun Shield for the Arduino).
Please let me know if I should move this topic to a different forum.
