The forums are retiring and are now closed for new topics and comments. The existing content will remain online and accessible through 2020 to provide everyone the opportunity to save any relevant information. In the spring of 2021, these Community forums will be taken offline.

Search for bidirectional in Topics


Bidirectional PIR motion

Hi everyone..I'm an absolute beginner in arduino and have a simple scenario i'd like to program.I have 2 PIR motion sensors in a passage or corridor.If i pass from PIR1 to PIR2 i want a relay to activate a green light.If i pass from PIR2 to PIR1 i want another red colour light to activate...BUT....not to reactivate the PIR1 triggered light.can anyone pleeeeeeease help.note: the PIR sensors are about 6 meters apartThanks in advance for any advice.

Question by MoesartSudan    |  last reply


Need Help with dc motor bidirectional controller circuit.

Hello all i need some help with driving 3 dc motors bidirectional with pots. Im looking at something like this that i can make that will drive 3 motors with 3 pots not just 1 here are the motors and im going for torque not speed. Thank You

Question by skullkeeper80    |  last reply


How to control 100 bidirectional DC motors?

Hi,  I'm trying to control 100 DC motors using a microcontroller (Arduino Mega) The motors run on 1.5V and have a operational current of 40mA. 1) Each motor must be able to rotate clockwise and counter clockwise 2) The motors must be able to move independently     (though direction of the motors at any one time will be the same)      eg. at time = 0; motor 1,20, 30, 45 will rotate CW            at time = 10; motor 20, 35, 80 will rotate CCW 3) Using minimum amount of pins from the Arduino (Shift Register ?) How should i go about doing this ? I have tried using L293D H-Bridge, but in order to control 100 motors,  i will need 50 H-Bridges and 200 digital output pins I'm thinking of a simpler circuitry (image attached) to control the motors. Digital output pins from the Arduino will contol the relay switches, and the DPDT relay will change the polarity of the the voltage supply. Will this work ?  Are there any smaller alternatives to the mechanical relay (transistor ?)  Can a transistor allow current flow in both directions ? I would really appreciate if you could provide some inputs and ideas as to how you would go about controlling a large amount of motors. Cheers!

Question by fujiapple    |  last reply


How would I make a bidirectional hand pump like an air mattress pump?

I'm looking for a resistance machine like a pneumatic  air mattress pump; two types. One pump could handle maybe 120 pounds pressure. The other would be for about 80 pounds.

Question by Peter1001    |  last reply



Electronic controls for CNC machine

I am looking to build 5-digit, 7-segment bidirectional counter with multiplexing display and input retention upon power failure. Input would be from an Incremental Handwheel Rotary Encoder. Any suggestions for a microprocessor ?

Topic by looiebwv    |  last reply


Unable to reverse direction of servo using arduino

I have arduino and a perfect code for moving servo to bidirection, but now i have facing problem of reversing the servo. I have replace three servos but having same problem. please help to detect is there is error in my arduino or servos?

Question by akshaydodkade    |  last reply


How to build a smart home for a recreation vehicle(RV)

There are already a bunch of projects doing similar things for houses but non for RV homes. I would like to communicate with my camper RV motor home and trying to understand and learn ways to do this. Here are some thought of requirements: - Data like temperatures, rain sensor, burglarizing alarm and a few webcams - Google App engine and Google GCM for the storage and bidirectional communication. - The RV API can let any device have bidirectional coms My thought is to us info from other HOUSE projects and do a mash-up to fit an RV, example: (thanks to Nikus at instructables) "Smart home with arduino" https://www.instructables.com/id/Smart-home-with-arduino/ The HOUSE in this project has a static ip no problem with coms but what about an RV? There are a number of questions like I think the RV will have problem with a static IP or maybe not any ides on this would be grate? Why do most project use the Arduion over the Raspberry pie what would be most suitable for my project? If anybody here have done this or want to contribute with knowledge it would be a grate

Topic by erikswed    |  last reply


Input on 3D-Printer controller-Config with MKS Rumba32, TFT35, TMC2130 SPI-bi

Hi togetherI want to mod an existing printer (TevoTarantula, non-Pro with a 8bit-Arduino Mega) to a new "brain". My plans on using: Board: Rumba32 (Makerbase MKS Rumba32, https://www.aliexpress.com/item/4000897233366.htm... Drivers: TMC2130 in SPI-Mode (https://www.aliexpress.com/item/32842401050.html) Display Option 1: TFT35-E3 V3.0 (https://www.aliexpress.com/item/4000349509983.html) Display Option 2: LCD 12864 (https://www.aliexpress.com/item/4000249447520.htm...)Now... I know, that i maybe have to mod the board to make the bidirectional SPI work. https://aus3d.com.au/image/catalog/products/rumba3... from Aus3D seemed to have a problem. Unsure if Makerbase has the same problem. Will see.Anyway: I am unsure if i can get the TFT35 V3 to work with the rumba32. All sources i can find have examples with the Rumba+ which is 8bit (Atmega2560).So...What would be your suggested approach to make it all (MKS Rumba32, TMC2130 SPI bidirectional, TFT35 V3) work?

Topic by Orngrimm    |  last reply


What would be a suitable serial protocol? Answered

I'm currently working on programming a serial interface to put onto I/O devices (number pad, LCD, sensors, secondary microcontroller...) in order to reduce the amount of I/O pins and external connections needed. The only requirements are that it needs to use only two wires (excluding power), and it needs to be bidirectional. Ideally, I'd like to avoid anything that needs too much processing of data before transmission (like adding extra bits to prevent a string of '1's from setting off the error protection). Hopefully, this project will end up as an instructable at some point, so what would be a suitable protocol that would be compatible with common microcontrollers? Thanks in advance.

Question by The Skinnerz    |  last reply


Does anyone know anything about this typewriter interface?

The typewriter is an AEG Olympia ES-95i. It's a big beige electronic machine from maybe the late 70s or early 80s.On the back there is a 20 pin rectangular male connector with 2 rows of 10 pins. If I connect random pins with something metal, it types various characters. I'm wondering if anybody knows what kind of interface this thing might use so I can go about connecting it to my computer.EDIT1:I've found a bit more random information about this type of device which might help:http://www.atarimagazines.com/creative/v9n6/133_Praxis_makes_perfect_Oli.phpApparently Olympia made another typewriter in the same line that was basically the same as a bytewriter model. Irritatingly the article says the bytewrite provides no technical information "other than the pin-out assignments for the connector. "It would appear from the rest of the article that the connector might be some kind of modified centronics interface.I'll try to get a picture up soon.EDIT2:Here's the photo. Whatever it is I hope it turns out to be bidirectional so I can use this as a tty :).

Question by pharoah    |  last reply