Unanswered Questions
364 questions with no upvoted or accepted answers
4
votes
0
answers
425
views
Rotary Encoder with interrupts - erratic behaviour
I'm trying to change my working rotary encoder code (stolen from here) to an interrupt-based code on my Mega2560. The trouble is that the result behaves very erratically, even though the physical ...
4
votes
0
answers
76
views
Can I use regular pins (Example: D2, A3, etc...) as serial (RX, TX)?
Python/Arduino Beginner here...
I have a DFplayer I am trying to hook to my Arduino and I want to hook it up through the regular pins instead of the RX and TX pins, but I've not been able to find ...
4
votes
0
answers
718
views
ArduinoDue - Matlab: SerialUSB.write() sends ASCII?
I'm trying to get some binary data from an Arduino Due to Matlab.
Basically this is the setup:
Due:
byte usbMsg[33]= {0};
// filled with dummy as example
usbMsg[1] = '00000001';// in[3];
usbMsg[2] =...
3
votes
0
answers
78
views
nano 33 BLE problems with reading RC signal
I'm using an Arduino Nano 33 BLE and a L293D motor driver to control a three-wheeled RC robot. The sketch I'm using worked fine with my Uno Rev3, but I've moved to the Nano for size/weight reasons, ...
3
votes
0
answers
211
views
220v lightbulb gradual dimmer
I am trying to turn my incandescent bulb gradually,say its brightness should go from zero to 100% in 10 mins. In doing so I found the following code and it works well but it's not as gradual as I ...
3
votes
0
answers
105
views
My port is grayed out?
Hello I have a question on why my port is grayed out when I go to upload?
I’ve watched so many YouTube videos on what’s the problem and have been trying to do everything but just nothing seems to work!...
3
votes
0
answers
204
views
Black screen when using higher SPI-speed for RA8857 LCD-controller
I'm using an Arduino Due that talks via SPI to an LCD (800x480) with the RA8875 controller chip.
The most recent datasheet I could find is: RA8875 datasheet.
Everything works as expected when using ...
3
votes
0
answers
713
views
Getting atsam3x8e (Arduino Due) to work
I decided to make a pcb based on the atsam3x8e (microcontroller used in Arduino Due). For the design I copied most of the layout that I found on this site and looked at the official Arduino Due ...
3
votes
1
answer
2k
views
Creating a sine wave with a DAC and feeding it back
I want to produce a digital sine wave, send it to DAC0, and then receive it back as input on A0 and plot the graph. I am using an Arduino Due. I wrote the following code:
#define maxSamplesNum 120
#...
3
votes
0
answers
653
views
Arduino nano clone problem with interrupt on falling edge on pin 2
I've s 1Hz square wave coming from a DS1307 SQW/OUT pin going into pin2 on the Nano that is set up as input with internal pullup enabled.
I've set up the interrupt on falling edge but I can't get the ...
3
votes
0
answers
601
views
Do software SPI read from a register using shiftin()
How to read from a register using software SPI, presumably shiftin()?
It works using the builtin SPI library + hardware SPI.
I seem to be able to write but not read using manual shiftin()/shiftout()...
3
votes
0
answers
378
views
Connecting Arduino Due's DAC output to pc sound card with protection
I would like to connect the DAC outputs of my arduino board to my pc sound card input so that I can use my sounds card as an osciloscope.
I have two questions:
1- if I don't use an amplifier, how ...
3
votes
0
answers
129
views
Reading Reveive Hold Register from USART in SPI Mode on Arduino Due
Sending with this function here works fine:
uint16_t usart0spiTransfer16(uint16_t spiMessage16) {
uint16_t sdo = 0;
byte firstByte = spiMessage16;
byte secondByte = (spiMessage16 >> ...
3
votes
0
answers
323
views
Arduino Due upload firmware issue
I have Arduino Due on SAM3x8e. I'm on Ubuntu 14.04. Before today I uploaded firmware via terminal using those commands:
$ stty -F /dev/ttyACM0 speed 1200 cs8 -cstopb -parenb
$ /home/q/apps/devel/...
3
votes
0
answers
883
views
Arduino Due native programming port
Arduino does not recommend to program the Due board via Native port as it is not reliable:
If the MCU crashed for some reason it is likely that the soft erase procedure won't work as this procedure ...