Beagle Board - beagleboard.org
Reed KaczmarekJeffrey CalhounJacques St. LouisJon Key
Published

2Hot2Handle

Using a BeagleBone Black, this coffee temperature detector works in an Internet of Things to create a comprehensive and useful display.

IntermediateFull instructions provided1,135
2Hot2Handle

Things used in this project

Hardware components

BLE 4.0 USB Dongle
×1
cc2650 Sensor Tag
×1
BeagleBone Black
BeagleBoard.org BeagleBone Black
×1
LED (generic)
LED (generic)
×3
Buzzer
×1

Story

Read more

Schematics

BeagleBone Schematic

We used Eagle CAD to draw the circuit related to the BeagleBone Black.

Code

SensorTag_BLE

Python
This is the script we run on the beaglebone black to connect with the sensortag and to display the results.
import binascii
import pexpect
import sys
import time
import Adafruit_BBIO.GPIO as GPIO

def floatfromhex(h):
    t = float.fromhex(h)
    if t > float.fromhex('7FFF'):
        t = -(float.fromhex('FFFF') - t)
        pass
    return t

GPIO.setup("P8_18", GPIO.OUT) #BLUE LED
GPIO.setup("P8_14", GPIO.OUT) #RED LED
GPIO.setup("P8_16", GPIO.OUT) #GREEN LED
GPIO.output("P8_18", GPIO.LOW)
GPIO.output("P8_14", GPIO.HIGH) #RED LED ON
GPIO.output("P8_16", GPIO.LOW)
bluetooth_adr = 'C4:BE:84:71:0D:80'
tool = pexpect.spawn('gatttool -b ' + bluetooth_adr + ' -I')
tool.expect('\[LE\]>')
print "\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nPreparing to connect...\n\n\n\n\n\n"
tool.sendline('connect')
time.sleep(1)
# test for success of connect
tool.expect('\[CON\].*>')
print "\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nConnected!\n\n\n\n\n\n"
GPIO.output("P8_18", GPIO.HIGH) #BLUE LED ON SINCE BLE IS CONNECTED
time.sleep(1)
ready_temp = 40
print "\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nPick a Profile (by number):\n1-Tough Guy, 2-Hot Head, 3-Medium Man, 4-Lukewarm Larry, or 5-Ice-Cold Izzy\n\n\n\n\n"
name = raw_input()
if(name == '1'):
    ready_temp = 50
else:
    if(name == '2'):
        ready_temp = 48
    else:
        if(name == '3'):  
            ready_temp = 46
        else:
            if(name == '4'):
                ready_temp = 44
            else:
                ready_temp = 42
print "\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nBeverage enjoyment temperature set at: ", ready_temp, " C, ", ((float)(1.8*ready_temp) + 32), " F\n\n\n\n\n\n"
tool.sendline('char-write-cmd 0x24 01')
tool.expect('\[LE\]>')
time.sleep(2)
ready_flag = 0
while True:
    time.sleep(1)
    tool.sendline('char-read-hnd 0x21')
    tool.expect('descriptor: .*') 
    rval = tool.after.split()
    objT = floatfromhex((rval[2] + rval[1]))
    objT_shift = ((objT/4))
    output_obj = ((float)(objT_shift)) * 0.03125
    ambT = floatfromhex(rval[4] + rval[3])
    ambT_shift = ((ambT/4))
    output_amb = ((float)(ambT_shift)) * 0.03125
    print "\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nToo Hot To Handle\nTemperature Dashboard:\n\nIR Temp: ", output_obj, " C,  ", (1.8*output_obj + 32), " F"
    print "Ambient Temp: ", output_amb, "  C,  ", (1.8*output_amb + 32), " F\n\n\n\n\n\n"
    if(output_obj > (ready_temp + 2)): #real use 55
        ready_flag = ready_flag + 1
    if((ready_flag > 3) and (output_obj < ready_temp)): #real use 53
        #CHANGE GPIO pins for LED
        GPIO.output("P8_14", GPIO.LOW)
        GPIO.output("P8_16", GPIO.HIGH)
        #PRINT TO MONITOR
        print "\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nYour beverage is no longer Too Hot To Handle!\n\t\t   Enjoy!\n\n\n\n\n\n"
        #BUZZER 3 BEEPS
        tool.sendline('char-write-cmd 0x50 01')
        time.sleep(0.5)
        tool.sendline('char-write-cmd 0x50 00')
        time.sleep(0.5)
        tool.sendline('char-write-cmd 0x50 01')
        time.sleep(0.5)
        tool.sendline('char-write-cmd 0x50 00')
        time.sleep(0.5)
        tool.sendline('char-write-cmd 0x50 01')
        time.sleep(0.5)
        tool.sendline('char-write-cmd 0x50 00')
        time.sleep(5)
        GPIO.output("P8_18", GPIO.LOW)
        GPIO.output("P8_14", GPIO.LOW)
        GPIO.output("P8_16", GPIO.LOW)
        break
GPIO.output("P8_18", GPIO.LOW)
GPIO.output("P8_14", GPIO.LOW)
GPIO.output("P8_16", GPIO.LOW)

Credits

Reed Kaczmarek

Reed Kaczmarek

0 projects • 3 followers
Jeffrey Calhoun

Jeffrey Calhoun

0 projects • 2 followers
Jacques St. Louis

Jacques St. Louis

0 projects • 3 followers
Jon Key

Jon Key

0 projects • 3 followers

Comments

Add projectSign up / Login