The Raspberry Pi is a credit-card sized computer that plugs into your TV and a keyboard. It’s a capable little PC which can be used for many of the things that your desktop PC does, like spreadsheets, word-processing and games. It also plays high-definition video. The design is based around a ...
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1answer
28 views
Appropriate electronics to use for scoring closest Nerf football air cannon shots?
Appropriate electronics and sensor technology to use for scoring closest Nerf football air cannon shots? The general concept would be to have a target area marked on the ground around a target device ...
0
votes
1answer
27 views
Slice of Pi wiring
I'm trying to wire a Ciseco Slice of Pi.
I need to break out the 3v3, 5v and GND solder pads as I need several of each. There's no track between the pad and the holes I want to use. I could wire ...
1
vote
2answers
67 views
How to create USB toggle switch controled by GPIO
I have Raspberry Pi setup as NAS. The storage is external HDD powered through USB. I would like to encase this whole thing in some nice box and still be able to easily use the HDD, without ...
0
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0answers
29 views
PIC16F767 as SPI Slave: Can't clock out data
I have a Raspberry Pi and a PIC16F767 connected via SPI. The rPi is the master, the PIC is the slave. I can write data to the PIC just fine and dandy, but I can't seem to get the PIC to clock data ...
1
vote
2answers
44 views
Sensing weight with strain gauge, InAmp, ADC & Pi
I have an SEN-10245 sensor for weighing objects (essentially a strain gauge). The goal is to capture data with a Raspberry Pi, so the signal from the weight sensor needs to be amplified and then ran ...
2
votes
1answer
53 views
Understanding 74LVC245 datasheet and current source/sink
I'm using a SN74LVC245A (datasheet) to shift 5V TTL down to 3.3V so I can read the signals with a Raspberry Pi.
However I am getting really weird results (a 60Hz input signal is picked up by the Pi ...
1
vote
3answers
98 views
Proper usage of a MOSFET to control USB
On the RaspberryPi.SE it was suggested that one can use MOSFET BS170 to switch a USB device on and off by a GPIO pin (3.3V). I need to get 500mA to power a GSM dongle; the voltage drop should ...
1
vote
1answer
57 views
Breadboard Wiring with Seven Segment Display
So I'm planning on building a skee ball machine and as I've been looking into it I've decided to use some seven segment displays from here:
As I've looked into this more I know I need a breadboard ...
0
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0answers
53 views
Is it possible to do an AM transmission using Raspberry Pi for transmitting analog TV signal?
I have a Raspberry Pi model B and I want to transmit a TV signal using the TX pin on the Raspberry Pi.
The TV signal enters the Raspberry Pi from the USB port using RTL-sdr.
Is it possible to do ...
1
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1answer
72 views
What is wrong with this SPI implementation
I designed a system with RaspberryPi and STM32F407's, communicating with each other via SPI interfaces.
For the last 3 months, tests were OK but yesterday a RaspberryPi and 2 of STM32F407's SPI ...
3
votes
3answers
312 views
Can I screw up my board by guessing which RS232 pins are which?
I have a Raspberry Pi that I want to hook up to a serial (RS232) cable. I've found and read some information about this, so I know what pins on my RPi are Rx/Tx/3.3V/Gnd...
Now the cable I'm hooking ...
2
votes
2answers
130 views
Is a N-Channel Mosfet save/reliable for level shifting UART from 3V3 to 5V?
I am busy with a design that needs to connect a Raspberry Pi to an Arduino via UART.
Previously I have designed a circuit that worked okay.
But now I want start using SMD components and is planing ...
0
votes
0answers
33 views
Why mobile/raspberry-pi charger configuration mention both volts and current? [duplicate]
For example, a standard charger for RaspberryPi menetions 5V/1.5A, some mobile charger mentions like 5V/0.5A . Now, it might sound like a noob question, but isn't Mobile/Raspberry-Pi or any other ...
2
votes
1answer
66 views
Laser controller project
The context is that I want to build a tunnel laser effect, that modulates the angle of the cone according to a sine wave. The purpose being, to create a cool Borg weapon effect for a Star Trek Borg ...
1
vote
1answer
60 views
Detecting vehicle on parking spot
For a project we're working on we need to detect if a car is standing on a parking spot.
We're using an ultrasonic sensor for this, SRF05. While using the correct timings we can only sense for about a ...
6
votes
3answers
493 views
Can I do this tutorial without a potentiometer?
I am trying out online tutorial to practice python and Raspberry Pi.
I am currently following this tutorial.
It says a potentiometer is needed, but I don't have one. The lcd I have is JHD162A
What ...
2
votes
3answers
83 views
Do you always need a GPIO expansion chip when using i2c?
SUMMARY:
I'm trying to learn the basics of understanding how to wire up a simple circuit using the i2c. I'm wanting to build just a simple project involving an LED and a push button with my raspberry ...
1
vote
1answer
140 views
Driving a LED matrix wall clock display (e.g. 64x16) from a Raspberry Pi?
My goal is to create a single-colour LED matrix display to show world times for several cities - e.g.:
...
3
votes
2answers
144 views
Cannot get a digital square wave on oscilloscope from the GPIO of the Raspberry Pi?
ENVIRONMENT:
Running "Raspbian" on Model_B Raspberry Pi (Revision 2) w/ ribbon expanding the GPIO out onto a Breadboard as shown in the following image.
SETUP
Here is a close up of the GPIO ...
1
vote
1answer
96 views
How many LED lights can 1 Raspi control
I asked a question on Raspberry Pi Beta regarding Using one Raspi to control long (>100ft) of 5V LED strip, one answer in particular I found this answer useful, with a further comment which advised me ...
1
vote
1answer
54 views
Connecting a current follower to a Raspberry Pi with an MCP3008
One of the experiments I conduct in an instrumental methods class is the construction of a rudimentary spectrophotometer described in the Journal of Chemical Education (link here if you have access to ...
0
votes
3answers
106 views
Serial connection between Raspberry Pi and Roomba
I have a Raspberry Pi with this FTDI cable and a Roomba 560. The Roomba has an SCI port to allow for control of the roomba via serial. I installed the PySerial library on the pi and send valid ...
9
votes
5answers
721 views
Control the hardware of an old phone using a Raspberry PI
I have a very old phone (60 years old) and I want to control its part using a Raspberry PI:
Microphone & speaker from the head set
The bell
The dial wheel
I have the electric circuit but don't ...
1
vote
1answer
156 views
How to modify DS1307 RTC to use 3.3V for Raspberry Pi?
I bought DS1307 RTC but it is 5V so it can't be connected to the Pi. I know it can be modified to use 3.3V by removing 2 resistors. This sensor is different than the adafruit kit so I am not sure ...
0
votes
1answer
39 views
What are the LE (latch enable) and the CLK (serial Clock) pins on the TQM8M9077?
I'm new here, so bear with me. I'm working on a sdr board for a raspberry pi and I have selected the TQM8M9077 as my DVGA. While looking at its datasheet and I came upon a few questions. What are the ...
1
vote
1answer
117 views
Using a FTDI to USB adapter with a raspberry pi and a roomba [closed]
I'd like to control a Roomba 560 using its 8-pin mini din SCI port. I've seen other people do this successfully but I'm still unclear on how exactly to go about this. I was planning on using an USB to ...
3
votes
2answers
91 views
External power for Raspberry Pi USB device
The Raspberry Pi's USB ports can only supply about 100ma of 5V current; this comes directly off the 5V input power to the board. The usual solution is to use a powered hub to support devices that ...
0
votes
1answer
254 views
How to wire external power supply on stepper motor
I followed this tutorial to setup my stepper motor.
Now my stepper needs 12V and not 5V. So I was wondering how I can add an external power supply without destroying my pi.
I found this:
But it ...
1
vote
3answers
206 views
Step up DC-DC converter for powering Raspberry Pi from batteries
I will power a Raspberry PI with 4 NIMH batteries, but they quickly lose charge, and end up at 3V instead of the 5V needed. I was wondering about a DC-DC step up converter.
I want a converter that ...
0
votes
0answers
47 views
Using PIC16F707 and Raspberry Pi for Touchscreen display
I've been asked to make a static touch screen for a store display with a very low budget.
Due to the cost limits and large number of 'buttons' required, I've considered the PIC16F707 since it has 32 ...
8
votes
3answers
995 views
Breadboarding a Raspberry Pi
Ok, long time reader first time asker on this parcticulair stack-exchange.
I am rather new to electronics, I've done some simple projects like Blinking Lights, alarms that go on when its dark and a ...
0
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0answers
95 views
Snapdragon 200 vs Raspberry Pi
I and a few friends are creating our own games console, and I would like to ask a question on our behalf. We're all teens, so making our own Hardware is implausible. So, we were considering Either a ...
0
votes
1answer
73 views
Raspberry pi with direct relay
I have a very back to basics question.
I've been using a 5v relay with the raspberry pi. The relay trigger is connected directly to an output pin and the other side is connected to the ground of the ...
2
votes
3answers
107 views
Why does my switch need to be wired in this fashion?
Today was my first foray into electronics since high school, in the form of some simple Raspberry Pi experiments. I managed to get a circuit working where a switch controlled an LED with a ...
1
vote
1answer
142 views
RaspberryPi I2C sensor - capacitor's role
I'm new here and the same goes to my electronics "history". I like to understand things I'm dealing with even if I wasn't provided with a sufficient knowledge background at schools.
What I'd like to ...
2
votes
1answer
100 views
Tradeoffs of XBee vs. Wifi for remote sensor & camera
I'm planning to build a remote sensor for my driveway gate, which is about 250' from the house (line of site). The basic requirement is to notify my HA system when the gate opens or closes, but I ...
3
votes
1answer
131 views
Externally Powered USB Port
I have a Raspberry Pi and it requires a Externally Powered USB hub to run Portable HDD on it.
So what if I connect +5 and GND port of the USB Client to external power source of 5V-1A directly rather ...
2
votes
1answer
185 views
Reading and writing CAN messages through ELM327
I have an OBD-II cable, and an UART-to-OBD-II board which has the ELM327 IC in it. I want to communicate with my ECU by sending-receiving CAN messages. Is it possible to communicate through ELM 327?
...
0
votes
0answers
332 views
Digital Potentiometer (MCP4131) with Raspberry Pi
I'm very new in electronic stuff. I'm used to develop for desktop and mobile applications not for hardware products.
I try to wire up my Raspberry Pi board with a MCP4131 Potentiometer. But it's not ...
2
votes
3answers
179 views
Logic level converter for H-bridge and UART for Raspberry Pi
Here is my situation:
I'm using a raspberry Pi to control a H-Bridge. The H-Bridge is not tolerant of both it's inputs being high logic value, which causes a short through the transistors, bypassing ...
1
vote
4answers
103 views
Check if electrical current exists in high voltage
I'm thinking about a simple home automation project, containing a Rasberry Pi, a Sainsmart SPDT Relay, I would like to switch the state of a ordinary bulb (ON , OFF) using both the relay and the old ...
-1
votes
1answer
70 views
Need +9V power supply for breadboard (3x Stepper motors). Tried Arduino wall wart [duplicate]
I need to supply +9V to three stepper motors on a breadboard with driver carriers (see parts below). Its too much for my raspberry pi to handle, apparently. I was able to power and control a single ...
0
votes
0answers
66 views
Hobby King 30A ESC 3A UBEC AS a voltage regulator
I wanted to efficiently step down 11.1V into 5v for my raspberry pi so i ordered (after reading many forums suggesting) this 5V UBEC thinking it would be simple switching regulator with two wires ...
0
votes
0answers
138 views
Setting up RFM12Pi v2 on Raspberry Pi
I recently bought a RFM12 v2 receiver and connected it to my Raspberry Pi. I also have some transmitters but I can't make all of this work.
When I start my Raspberry Pi, the green LED on the RFM12 is ...
0
votes
1answer
380 views
RC Car mounted Raspberry Pi runs out of juice
I'm trying to make a Tamiya Blackfoot RC car run on a Raspberry Pi.
I've written a small C program for controlling the servo and the ESC/motor with a wireless gamepad. Everything is working fine ...
1
vote
0answers
72 views
MOSFET to be switched by a raspberry pi
My raspberry pi produces a 3.3V on it's GPIO. I want to buy a through hole MOSFET so I can simulate touch-events on a smartphone screen like this video. I'm trying to find something on Digi-Key, but ...
0
votes
2answers
335 views
retail store visitors counter [closed]
I want to count how many people every day visits our store. In store has two entrances. Second entrance is not used often. Entrance gate is about 1.5m wide. I plan to attach some device to Raspberry ...
1
vote
0answers
62 views
small, fully functional pc boards and kinect (example Raspberry Pi) [closed]
I have discovered that people trying to prototype a kinect controller with Raspberry Pi have had limited to no success. I found some people with limited success with PandaBoard. I am now interested ...
1
vote
2answers
192 views
Can ATmega88 be run at 3.3V with internal clock?
I want to use a few ATmega88s with Arduino bootloaders to act as I2C stepper drivers and temperature controllers that will interface with a Raspberry Pi. The thing is just that it seems the RPi ...
2
votes
2answers
302 views
RGB LED brightness levels
Do RGB LEDs have very different brightness levels?
I'm running an RGB LED (common cathode) via some TIP120 transistors, controlled from a raspberry Pi.
There is a 5v feed from the rPi.
Initially I ...
