0
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I'm using a Conrad DCF77 to get RTC on Beaglebone Black and wiring it so:

1--> GND | 2--> VCC 3,3 V | 3--> One of the gpios (P8_11)

To read the Signal of the DCF Antenn I wrote the code:

import Adafruit_BBIO.GPIO as GPIO
import time
GPIO.setup("P8_10", GPIO.OUT)
while True:
    new_switch_state = GPIO.input("P8_11")
    print(new_switch_state)

Result is

0
0
0
0
0
0
.
.
.
.

So no signal is read. Could you help ? THX!

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1
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The data sheet says: -

  1. Earth
  2. Operating voltage 1.2 … 1.5 V- (although the German DS appears to say 15 V)
  3. DCF output
  4. DCF output inverted

Outputs 3 and 4 of open collectors npn max. 30 V 1 mA

So it looks like you have powered it with too much voltage (unless you read the German DS) and you don't understand what an open collector is - it requires a pull-up resistor.

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  • \$\begingroup\$ Thanks for the answer. I've added a pullup resistor of 10kOhm. \$\endgroup\$ – Ben Jo Feb 1 '18 at 19:22
  • \$\begingroup\$ @BenJo did it work? \$\endgroup\$ – Andy aka Feb 1 '18 at 19:25
  • \$\begingroup\$ Nope :P unfortunately \$\endgroup\$ – Ben Jo Feb 1 '18 at 19:28
  • \$\begingroup\$ Keep working at it then LOL \$\endgroup\$ – Andy aka Feb 1 '18 at 19:29

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