diff --git a/src/config.py b/src/config.py
new file mode 100644
index 0000000..5a0ce96
--- /dev/null
+++ b/src/config.py
@@ -0,0 +1,2 @@
+from abc import Singleton
+
diff --git a/src/pwm.py b/src/pwm.py
new file mode 100644
index 0000000..ceb1be4
--- /dev/null
+++ b/src/pwm.py
@@ -0,0 +1,73 @@
+#import RPIO
+import RPi.GPIO as GPIO
+import time
+from datetime import datetime
+from datetime import timedelta
+switch = 15
+pwm = 14
+fan_speed =18
+#RPIO.setup(switch, RPIO.OUT)
+
+#RPIO.output(switch, True)
+
+# RPIO.PWM.setup()
+#fan = RPIO.PWM.Servo(0, 40, 1)
+GPIO.setmode(GPIO.BCM)
+GPIO.setup(switch, GPIO.OUT)
+GPIO.setup(pwm, GPIO.OUT)
+fan = GPIO.PWM(pwm, 25000)
+
+GPIO.setup(fan_speed, GPIO.IN, pull_up_down=GPIO.PUD_UP)
+global last_ts
+global current_ts
+global diff
+diff = timedelta()
+last_ts = datetime.now()
+current_ts = 0
+global counter
+counter = 0
+def speed_callback(channel):
+    global last_ts
+    global current_ts
+    global diff
+    global counter
+    current_ts = datetime.now()
+    if current_ts != 0 and last_ts != 0:
+        diff = current_ts - last_ts
+    if diff.seconds < 1:
+        counter+=1
+    else:
+        rpm = (counter/2)*60
+        print("{} ||| {}                    ".format(counter, rpm), end="\r")
+        last_ts = current_ts
+        counter = 0
+#    print("{}                    ".format(rpm), end="\r")
+#    print("{:d}     | \t{:.2f} | \t{} | \t{} | \t{}".format(diff.microseconds, rpm, diff, current_ts, last_ts), end="\r")
+    
+
+GPIO.add_event_detect(fan_speed, GPIO.FALLING, callback=speed_callback)
+
+try:
+    GPIO.output(switch, True)
+    step = 10
+    c = 0
+    direction = 1
+    diff=timedelta()
+    fan.start(c)
+    while True:
+        if c == 100:
+            direction = -1
+        elif c == 0:
+            direction = 1
+        c += step*direction
+        fan.ChangeDutyCycle(c)
+#        print("{}                                                ".format(c))
+        time.sleep(5)
+except KeyboardInterrupt:
+    pass
+finally:
+    fan.stop()
+    GPIO.output(switch, False)
+    GPIO.cleanup()
+
+
diff --git a/src/spi/spi.py b/src/spi/spi.py
new file mode 100644
index 0000000..ae55a49
--- /dev/null
+++ b/src/spi/spi.py
@@ -0,0 +1,36 @@
+from abc import Singleton
+import RPi.GPIO as GPIO
+import spidev
+
+
+class LowLevel(metaclass=Singleton)
+    def __init__(self):
+        self.__spi = spidev.SpiDev()
+        self.__spi.open(0,0)
+        self.__spi.mode = 0
+        self.__spi.max_speed_hz = 1000000
+        GPIO.setmode(GPIO.BCM)                               
+
+
+    def __activate(self):
+        self.__spi.cshigh = False
+
+    def __deactivate(self):
+        self.__spi.cshigh = True
+
+    def retrieve_adc(self, channel):
+        if channel > 7 or channel < 0:                   
+            return None
+
+        GPIO.output(pin, True)     
+        hchbit=channel >> 2                              
+        lchbits = channel & 0x03                         
+        to_send = [ hchbit | 0x06, lchbits << 6, 0x00 ]  
+        self.__activate()
+        r=spi.xfer(to_send)                              
+        self.__deactivate()
+        GPIO.output(pin, False)    
+        highbyte = r[1]                                  
+        lowbyte = r[2]                                   
+        value = (highbyte << 8) | lowbyte                
+        return value
diff --git a/src/test.py b/src/test.py
new file mode 100644
index 0000000..3a13bc0
--- /dev/null
+++ b/src/test.py
@@ -0,0 +1,84 @@
+#!/usr/bin/python
+
+import spidev
+import time
+import RPi.GPIO as GPIO
+from decimal import *
+
+tnom = 25
+rnom = 10000.0
+corr = 4800
+temp_gpio = { 
+        0: {
+            "BCM": 20,
+            "Rk": 9770.0 #9770,
+        },
+        1: {
+            "BCM": 26,
+            "Rk": 10000.0
+            } 
+        }
+
+GPIO.setmode(GPIO.BCM)
+for k in temp_gpio:
+    GPIO.setup(temp_gpio[k]["BCM"], GPIO.OUT)
+    GPIO.output(temp_gpio[k]["BCM"], False)
+
+def read_spiADC(spi, channel):
+    if channel > 7 or channel < 0:
+        return []
+    GPIO.output(temp_gpio[channel]["BCM"], True)
+    hchbit=channel >> 2
+    lchbits = channel & 0x03
+    to_send = [ hchbit | 0x06, lchbits << 6, 0x00 ]
+    spi.cshigh=True
+#    time.sleep(0.01)
+    spi.cshigh = False
+    r=spi.xfer(to_send)
+    spi.cshigh = True
+    GPIO.output(temp_gpio[channel]["BCM"], False)
+#    time.sleep(0.01)
+    highbyte = r[1]
+    lowbyte = r[2]
+    value = (highbyte << 8) | lowbyte
+    return value
+
+def calc_temp(adc_reading, channel = 0):
+    rser = temp_gpio[channel]["Rk"]
+    r = (rser/(4095/adc_reading - 1))
+    r = r - corr
+    t = r/rnom
+    if t < 0:
+        t = t * -1
+    t = float(Decimal(t).ln()) / 4050 + 1.0/(tnom + 273.15)
+    t = 1/t
+    t = t - 273.15
+    return t
+
+#GPIO.output(temp_gpio[1], True)
+#while True:
+#    pass
+
+spi = spidev.SpiDev()
+
+spi.open(0,0)
+spi.mode = 0
+spi.max_speed_hz = 1000000
+while True:
+    chan0 = read_spiADC(spi, 0)
+    chan1 = read_spiADC(spi, 1)
+    r0 = 0
+    r1 = 0
+    t0 = 0
+    t1 = 0
+    if chan0 != 0:
+        r0 = rnom/(4095/ chan0 - 1)
+        t0 = calc_temp(chan0, 0)
+    if chan1 != 0:
+        r1 = rnom/(4095/ chan1 - 1)
+        t1 = calc_temp(chan1, 1)
+    print("{:d} R={:d} T={:.2f} |\t| {:d} R={:d} T={:.2f}".format(chan0,int(r0), t0, chan1, int(r1), t1), end="\r")
+    time.sleep(0.25)
+#    print(str(chan0) +" R=" + str(int(r0)) + " T=" + str(t0) +" |\t| "+str(chan1)+" R="+str(int(r1)) + " T=" +str(t1), end="\r")
+
+spi.close()