13
votes
Accepted
Multiple I2C sensors with the same address
If you're using MPU6050 IMUs, there's an easy trick: put them all on the I2C bus, and connect each IMU's AD0 pin to a separate digital pin on the Arduino[*]. When you want to read from a specific IMU, ...
- 1,588
5
votes
Accepted
How important is the INT pin of the MPU6050 (GY-521)?
The INT is the interrupt signal, usually open-drain output and you can connect many of them to the single MCU interrupt line (but you have to check all devices which ones are ready). The LOW level ...
- 4,777
5
votes
Accepted
Interface with mux-controlled LED rope
You're using a 16-channel analog multiplexer to talk to your devices (the LED ropes) via a single pin on your Arduino. "Multiplexer" is just a fancy name for a switch; "analog" ...
- 594
5
votes
Accepted
Need help with 2X3 matrix for braille
First of all, may I say "Thank you" for helping your friend like that? I cannot think of a better way to use an Arduino than as a driver for a Braille display like you describe!
As you know, Braille ...
4
votes
Need help with 2X3 matrix for braille
Each character will be 6 bits (so let's use a byte to store it) and we'll use the following bit to LED mapping
bit0 bit1
bit2 bit3
bit4 bit5
Now you just need an array of bytes where each byte ...
- 393
3
votes
Interface with mux-controlled LED rope
After reading your github page, I came to realize that:
you do not require full color control, but only setting the strips to
full red or full blue
you are using MOSFETs for driving them.
Given ...
- 43.9k
3
votes
Multiple I2C sensors with the same address
You can also get I2C Multiplexers such as the TCA9545A that can split one I2C line into 4 buses. I have connected up to 9 MPU9150 on one line with that.
- 41
3
votes
Accepted
Why is Serial.begin(9600) interfering with my multiplexor functioning?
(Digital) Pins 0 and 1 are used by the hardware serial port you initialize with Serial.begin() on a classic Arduino like an Uno.
With this type of board it is generally best not to use those for any ...
- 5,401
2
votes
Accepted
PWM multiplexing on Arduino nano
I've copied and slightly modified your diagram, as below. Note the added connections of R1, R3 cathodes to that of R2, and similarly for green and blue LEDs.
simulate this circuit – Schematic ...
- 8,870
2
votes
multiple multiplexer (4051) - how to process the inputs?
The 4051s are only useful, for your potentiometers. For leds, I'd use shift-registers. For buttons you could use input-shift-registers. Though there are better options. E.g. chips that can scan a ...
- 11.3k
2
votes
How to multiplex multiple displays?
The code instantiates two instances of the SevSeg class. This may or may not work. Really depends on if the class uses any resources are not meant to be shared between multiple instances of that ...
- 7,435
2
votes
Accepted
Using an Arduino and multiplexer for writing to multiple outputs
According to the analogWrite() documentation, apparently the trouble are that you have swapped the args.
The syntax are analogWrite(pin, value), so, the piece
//read the value at the SIG pin
...
- 56
2
votes
Accepted
Arduino I2C Multiplexing uisng TCA9548A
The TCA9548 is a switch.
You begin a transaction to it, change the channel that it allows through, and then end that specific transaction.
From that point on one and only one of the other two sensors ...
- 105k
2
votes
What are a few good ways to connect multiple I2C busses?
In an ideal world you would have your other sensor on a separate I2C bus. It can be done with software, but chances are you will have to re-write the library that supports it to use bit-banged I2C.
...
- 105k
2
votes
How do I connect 20 outputs and 20 inputs to an Arduino board?
Look for port expansion boards for the arduino, there are a lot of them many under a dollar. Typically they are in 8 or 16 channel designs. They probably will have PCF8574 or PCF8575 chips. These are ...
- 1,853
2
votes
Accepted
Multiplexer 74HC4067, conflict between channels
I gather it is part of a learning experiment. Logically this does not compute however there are many reasons something like this could happen. A bad IC is the first thing that comes to mind but they ...
- 1,853
2
votes
Using CD74HC4067 16-Channel Analog Multiplexer Demultiplexer is not working as expected
I finally managed to get a solution to my problem. There was a cabling and a software issue as well. Firstly, I pulled down the Signal with a 10K resistor. In this way I stopped having those random ...
- 51
2
votes
Accepted
What size diode should I use?
By the time you finish mucking around powering different devices from I/O pins (which have a limit to how much current they can source) and then install different diodes for each one, you are probably ...
- 38.5k
2
votes
Voltage reading problem in Arduino mega based 10 cannel battery capacity tester
Electric wires have resistance. Most of the time this resistance can be ignored, but this is not always the case. Specifically, if the wire is carrying a large amount of current, the voltage drop ...
- 43.9k
2
votes
Multiplexing three VFD tubes — why are the segments and the display timing incorrect?
I made a VFD clock using some really cool old DG10B tubes from an early calculator a year or so ago. I had a heck of a time getting it to work, until I decided try tackling one problem at a time, and ...
- 31
1
vote
Arduino SPI Multiplexer problems
Take a deep look into the library you are using to read the POT. Most HW and / or SW will take many readings & average them to remove the randomness and improve the accuracy of the ADC HW. It ...
- 7,435
1
vote
Accepted
Routing Matrix with a large number of I/O
I would use a port expander that uses I2C for communications. One example is the PCA9555. You can add up to eight by setting the address bits (A0-A2). This will give you up to 64 outputs to control ...
- 993
1
vote
Accepted
maintain state of a channel cd74hc4067
The whole point of a multiplexer is to only connect ONE channel at a time to the input. It is designed to send many different signals through one wire by time sharing. Normally data in some form is ...
- 16.5k
1
vote
Accepted
Binary addressing and coding to control a 96 input mux matrix
OK. First, how the multiplexer works. I have a page about multiplexers in which there is this example of the 74HC4051:
Depending on the "binary" input to A/B/C (shown as S0/S1/S2 on your schematic) ...
- 38.5k
1
vote
How does Peggy2 drive rows with 74HC154 Decoder?
If you look into the datasheet of 74HC154, you can see that each output has an Active Low State. Also in the schematic, the leds row part use a pnp transistor (see page two). As so, they will be ...
- 926
1
vote
Minimum number of Pins to use for multiplexing LEDs
It depends on the style of multiplexing.
For basic Row-Column multiplexing you have N=RC - the number of LEDs is the number of rows multiplied by the number of columns. The LEDs, of course, don't ...
- 105k
1
vote
Accepted
Avoiding false rising and falling edge when using demultiplexer
To do multiplexing with bounce.h you will need one bounce object per button. That's 64 bounce objects for an 8x8 matrix.
Then you only want to update the bounce objects for the group you currently ...
- 105k
1
vote
Using Capacitive Sensing Library with a 74HC4067 multiplexer
This is way late, but for anyone who runs across this, here was my solution. The two main thing is explicitly using analog input pins (which could be quantized to digital values in the software, and ...
- 111
1
vote
Issue with code for SDA/SCL TC9548A Multiplexer and HMC5883L sensors
I'm sure you have, but have you connected the grounds together?
Have you tried 1 sensor on SD/C0 and then moving it to SD/C1 it should stop working, so the fault has to be with SD/C0.
Looking at ...
- 5,637
1
vote
Multiplex 7 segment during delay (external IC?)
Perhaps a MAX7219 would do what you want.
The MAX7219CNG+ is a 8-digit serially interfaced LED Display Driver for LED matrix displays.
The MAX7219 is compact, serial input/output common-cathode ...
- 2,181
Only top scored, non community-wiki answers of a minimum length are eligible