Go to advanced search

by Ferdinand
Sat Sep 27, 2014 3:12 pm
Forum: General discussion
Topic: how to read/detect an input voltage spike?
Replies: 7
Views: 1537

Re: how to read/detect an input voltage spike?

Hello Alexbb, Use a d-flipflop (d-ff) to detect a spike. The toggle input can be set by the sensor. The Q output of the d-ff will be set (high). Now you can read the status of the Q output. After reading reset the d-ff (Q output -> low) for the next change of the sensor. Good luck with your project....
by Ferdinand
Mon Sep 22, 2014 12:33 pm
Forum: Automation, sensing and robotics
Topic: Control 2 dc motor with joystick and L293D
Replies: 3
Views: 1478

Re: Control 2 dc motor with joystick and L293D

Hello Thomas,

I found this post:

http://www.raspberrypi.org/forums/viewt ... 9&p=354237

Good luck with your project.
by Ferdinand
Sat Aug 16, 2014 4:07 pm
Forum: Nederlands
Topic: GPIO pinnen aansturen tussen 2 raspberry`s
Replies: 6
Views: 1581

Re: GPIO pinnen aansturen tussen 2 raspberry`s

Hallo 1971ikke, Op hierondergenoemde site vind je python code om tussen 2 computers te communiceren (op hetzelfde netwerk). Je moet het zelf uitbreiden met python code om gpio pinnen te kunnen aansturen. In de zendende computer moet je het ip adres opgeven van de ontvangende computer. Op de ontvange...
by Ferdinand
Tue Aug 05, 2014 12:57 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: infra red remote control
Replies: 4
Views: 1250

Re: infra red remote control

Hi Bill, Take a look at this thread: http://www.raspberrypi.org/forums/viewtopic.php?f=44&t=74407 (Transistor for IR Transmitter) or http://lirc.org (Linux Infrared Remote Control) or otherwise post drawings, setups, software a.s.o. -->(small) details are very important! Good Luck with your project.
by Ferdinand
Wed Jul 02, 2014 11:51 am
Forum: Python
Topic: GPIO loop, stops
Replies: 11
Views: 3044

Re: GPIO loop, stops

Does your script run without relais?
-Spikes caused by your relais can halt your script.
-Use a second power supply for your relais.
-Avoid ground loops.
by Ferdinand
Sat May 10, 2014 11:59 am
Forum: Beginners
Topic: Alarm System question
Replies: 9
Views: 2952

Re: Alarm System question

Hi, --> This drawing is just an idea. The alarm circuit ( https://dl.dropboxusercontent.com/u/53885757/alarm.pdf ) is based on a voltage divider, see table below. Each switch is a zone and each zone has his own actions such as: alarm, delay to disarm alarm, only logging, sending email/sms, zone alar...
by Ferdinand
Wed Apr 23, 2014 12:14 pm
Forum: Beginners
Topic: Alarm System question
Replies: 9
Views: 2952

Re: Alarm System question

One wire will do your job. Make a ring of doorswitches. Solder over each doorswitch a resistor. Switch1 a resistor of 1K, switch2 a 2K resistor a.s.o. Solder the last resistor (the highest resistor) across the end points of the ring. Make a constant current source of 1 mA, (0.5 mA is also OK). When ...
by Ferdinand
Thu Apr 17, 2014 1:25 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Transistor for IR Transmitter
Replies: 25
Views: 13493

Re: Transistor for IR Transmitter

Hi Tom, Keep the following items in mind: - The bc337 is a small signal transistor and maybe causes your problems. Maybe the carrier frequency is a little to high (38 kHz) for this type of transistor and will not saturate properly. -instead of a transistor you may use a logic circuit such as a nand/...
by Ferdinand
Mon Feb 17, 2014 7:43 pm
Forum: Beginners
Topic: How many I2C devices can I connect to Raspberry Pi?
Replies: 9
Views: 6632

Re: How many I2C devices can I connect to Raspberry Pi?

The type of device isn't important but if 2 or more share the same address line then you cannot communicate with them. For example the TEA5767 and RDA5807M FM Radio module both use the same 0x60 I2C address. Individually they work fine on the Pi but I cannot connect both modules together because th...
by Ferdinand
Mon Feb 17, 2014 4:39 pm
Forum: Nederlands
Topic: Projecten
Replies: 1
Views: 860

Projecten

Hallo Toney, a) Wat denk je van een reactie snelheidsmeter? Zodra een ledje gaat branden dan moet je op een knopje drukken. Het tijdsverschil tussen het branden van het ledje en het drukken op een knopje is een maat voor jouw reactie snelheid. b) een python morse generator dat een ledje laat branden...
by Ferdinand
Sun Dec 01, 2013 2:45 pm
Forum: Automation, sensing and robotics
Topic: What if sonar beam doesn't come back
Replies: 18
Views: 2709

Re: What if sonar beam doesn't come back

The code has been a little bit modified. I placed comments near the important statements. To speed up the while True routine remove the comments and / or move it to the start of while True routine because Python is an interpreter! while True: time.sleep(0.1) #Send pulse to trigger GPIO.output(GPIO_T...

Go to advanced search