a technique for serial communications using software instead of dedicated hardware.

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Serial communication with two devices at once using pigpio?

I'm using the raspberry pi pigpio module to communicate with two other devices at once using two separate threads. The devices are connected to two different pairs of gpio pins. I need to adhere to ...
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0answers
92 views

Using INT interrupt line on PCF8574 I2C 8-bit IO-expander on Bit-banged RPi GPIO?

I am planning to use a triplet of RPi GPIO pins as an additional bit-banged I2C bus on my RPi. This will be run at a lower than typical rate (and level-shifted via a 3.3 to 5.0 V I2C shifter unit) so ...
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93 views

I2C repeated start with BitBanging not working - Pigpio library on Raspberry Pi B+

First post here on the forum! Been getting a lot of help here from all the past posts and I am grateful for such a great community. I have been trying to use Repeated Start by using the PIGPIO ...
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0answers
352 views

Problems Bit-Bashing an I2C Slave

I have a Pi B+ on which I'm trying to bit-bash an I2C Slave in C / C++ (code's pretty much C despite the fact I'm using g++ and .cpp files), utilizing GPIO 18 as my Clock and GPIO 17 as my Data. I'm ...
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2answers
550 views

Theoretical maximum data rate of GPIO pins

Is there a maximum data rate of the GPIO pins? I.e. if I wanted to bit-bang data through one of the pins, what kind of data rates could I achieve? Alternatively, what is the slew rate of a GPIO pin? ...
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3answers
6k views

How fast is GPIO+DMA? Multi I2S input

I want to connect multiple I2S ADCs to RaspberryPi and record multi-channel audio. I calculated that it requires copying GPIO input port to RAM at 3072kHz (or every 0.33µs). I want to do it using DMA. ...
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1answer
1k views

Raspberry Pi on AVC-LAN / IEBus

I'm planning on using my Raspberry Pi in my car as an XBMC server. I'll be able to select songs/videos using the Android remote control app, but it occurred to me that it would be really neat if I ...
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256 views

Interfacing external device using accurate high-speed clock signal [closed]

I need to interface device using specific synchronous protocol that requires clock signal within 1..2MHz. Period instability shouldn't exceed 10%. Also, in certain condition protocol requres clock ...
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3answers
1k views

Multiplexing 4-digit 7-segment display is flickering

I connected a 4-digit 7-segment display to the GPIO-port. It uses 8 ports for the LEDs and 4 ports for multiplexing via PNP-transistors. It is running so far with a loop written in C program: while(1)...
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3answers
10k views

Can Raspberry Pi reliably bit bang a 9600 baud serial and is there example code?

I am wondering how feasible it is to use bitbanging to drive a 9600 baud serial via the GPIO pins on the Raspberry Pi. Obviously, Linux is not a terribly good platform for bitbanging, as there is a ...
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How do I bit bang I²C master?

I've installed RPi.GPIO. It doesn't support I²C yet, but can I use it to bit bang I²C? I would just need the Raspberry Pi to be the master.