Questions tagged [spi]
Serial Peripheral Interface. Allows full-duplex serial communication from a master device to one or more slave devices arranged on a bus. Sometimes referred to as a 4-wire bus.
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SPI between Master arduino and Slave arduino
How can I send the string from Slave SPI to Master SPI?
I want to write code in Bare Metal.
The problem which I am facing is I can't make out what will be my blocking function in Master SPI code when ...
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Raspberry pi pico (Arduino core) not initialising SPI correctly for NRF24l01
I'm working on a project where i have a Raspberry pi Pico connected to a NRF24l01+ to send some data.
However i'm not recieving any data on the reciever and i think that its because the SPI bus is not ...
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ESP32-C3 SPI Class documentation/features?
ESP32-C3 has a nice feature called GPIO Matrix which allows to map most of it's peripherals to any GPIO pin. And it has feature called IO_MUX which allows direct & faster operations for some of ...
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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 ...
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SPI register read returns 0x00 or 0xff
I am trying to interface a Arduino Uno with an ASM330LHH using SPI. Whenever I try to read any register, I either get 0xff or 0x00 on the serial monitor
The code I am using:
#include <SPI.h>
#...
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How to use SPI to set/ read registers for a sensor (Avoiding need for Github Lib)
Ok so as some readers might have seen, my current project involves using MPU's. The idea is sending data via CAN bus to a controlling MCU to then send to a raspberry pi to perform the calculations ...
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Scheduling and BLE Read on demand
I'm building a data logging device with BLE capability using RFduino.
Sensors are read using timer interrupt to a buffer. When the buffer is full, then the whole buffer is written to SD card.
At the ...
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SPI communication between two Ethernet Shields (W5100)
I am a newbie to the world of IoT, I want to ask...
Is it possible to connect two Ethernet shields with SPI? And if yes, how can I codes them?
I have reference from http://www.gammon.com.au/spi and ...
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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()...
J Halcres
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Read from the SD card - ACMD41 times out
I'm trying to read from the SD card using an Arduino Pro Mini (3.3 V), Pololu micro-SD reader (the 3.3V one) over a SPI protocol.
I've tried both the SD library from Arduino SDK, and the Adafruit one....
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Slow I2C communication
To collect temperature and BPM, I connected a max30101 in my Heltec WiFi kit V3 with ESP32. The data collected are stored in arrays to extract statistical features from signals which an algorithm will ...
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Ability to connect 2 or more w5500 Modules and deal with them as objects
I wish to create a rudimentary ethernet in/out - switch/hub where I can (sort of) daisy chain my boards. (I don't wish to use a ethernet switch/router/hub)
One port would be acting as server
The ...
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SD card breakout sometimes does not initialise (SPI connection - Teensy 3.2)
I have connected this Adafruit SD Breakout to a Teensy 3.2 over SPI. Because Teensy 3.2 is 3.3 V, I've connected the 3.3 V pin of the Teensy to the 3V pin of the SD breakout.
See sketch below. I'm ...
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ESP32DevkitC-V4 interfacing ADS8698 (18 bit ADC)
I am currently working on an SPI interface to measure the voltage of an amplified sensor bridge signal. I am using an ESP32 module to control the device. Since I am logging the data to an SD card, I ...
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Why can't an Arduino/ATmega328 act as an SPI slave at anywhere approaching the maximum speed claimed in the datasheet?
The ATmega328 datasheet claims a maximum SPI slave speed of Fosc/4. For a chip clocked at 20MHz, that would be 5Mbps.
However, my tests show that even with no processing whatsoever in the interrupt (...
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SPI problem with Bitcraze PMW3901 sensors and Arduino NANO
I am currently trying to connect four Bitcraze PMW3901 sensors to an Arduino NANO, but I seem to have issues with the SPI. When I connect two sensors using the code below, it works perfectly: I am ...
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Stand alone Atmega328p-au
I'm trying to make a standalone arduino board with an OLED display using an Atmega328p. I never tried to make such a board using SMD components. I've soldered everything together except the OLED ...
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Using ICSP pins as SPI in Arduino Due
I am using two RFID sensors operating on SPI with arduino Due. They will not be operating at the same time.
Is it favorable to use the ICSP pins as SPI pins for one of them, or use them in a one ...
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Reading and writing to GD25B32CPIG flash memory
I recently removed a GD25B32CPIG flash memory chip from a commercial coin-operated arcade game. Apparently it has all the game's sounds stored directly on the chip. I decided to see if I can learn to ...
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SPI Arduino slave not recieving data correctly
Using an STM32L476RG Nucleo microcontroller board as the SPI master and an Arduino mega as a slave with pin 52 for SCLK, pin 53 for SS and pin 51 for MOSI on the Arduino. There is no issue with the ...
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nRF24L01 +pa +lna link does not communicate
I’m trying to create a link between two nRF24L01 units. Each nRF24L01+-based module (purchased) is connected to Arduino Nano on a custom-designed PCB.
The printed wiring is per the hardware ...
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Communication between two slaves via single SPI bus
I am trying to control both RC522 and lcd st7920 (128x64) via a single SPI bus on the NodeMCU esp8266. I am using Arduino core for my esp8266. Now in this portion of the code, I only want to display ...
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Start VL53l0X measurement failed
The initialization of the ToF fails with this code. I'm trying to frankenstein it with Radiohead RFM69, so far no luck.
// rf69_reliable_datagram_client.pde
// -*- mode: C++ -*-
// Example sketch ...
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My PIR sensor output changes but digitalread high all the time
This is my final project, I have to communicate with two wemos d1 mini by LAN. The problem is that when I read the state of the PIR sensor it is "HIGH" all the time, but when I connect the led light, ...
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Reading byte per byte from a txt file on SD Card without using the 512Bytes buffer
I am trying to read every sequenced-byte that is located on a txt file in the SD card. I have been reading quite a lot about the SPI and SD libraries, But I have found a lot of different information ...
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Reading data from SPI on ESP32-WROOM-32
I'm newbie with Arduino and need to do a short task: read data from SPI (sent by another microcontroller) and send to WiFi (by ESP32-WROOM-32).
I can't understand how to initialize and read data from ...
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Interfacing MAX6675 with Arduino Mega 2560
I'm trying to use a thermocouple k type and a MAX6675 IC. I bought the MAX6675 chip and made the circuit (just a 1 nf capacitor on +5 V and GND near the IC) with the help of the datasheet
I used the ...
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NFC PN532 SPI - Error: Timeout when waiting for ACK
I've been struggling to get the PN532 module working over SPI with an Arduino Uno.
I have the wires connected as follows:
SCK -> 13
MISO -> 12
MOSI -> 11
SS -> 10
VCC -> 5V
...
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NRF24l01+ works only when touching its antenna
I have two simple NRF24l01+ (with range of 200m) and two NRF24l01+ with range of 1km.and two socket adapter.
or what I have
and I have two good library with names RF24 and RF24-master . problem ...
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Not able to read the product ID from ADIS16260 Gyroscope Sensor
I have interfaced a ADIS1620 sensor to the Arduino UNO using SPI.I am having a bit of trouble here to read the product ID information from the ADIS1620.According to the datasheet here,
on page 11, it ...
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SPI or A0/A1: what is the best solution for pin allocation on an Arduino shield?
When you design an Arduino shield you want to make it compatible with a maximum number of shields that may be stacked with it on an Arduino (UNO). Considering the following two possible tradeoffs, ...
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How do you debug SPI connected devices?
EDIT: Changed the title to better express what I'm after.
I've been dabbling in connecting two Arduino Nano 3's with the RFM69HCW breakout for the past 5 days.. but got nowhere.
I've followed the ...
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How can I transfer multiple frames from the Arducam's fifo buffer to file without zero padding?
I've been unable to resolve a coding problem I've been having with the Arducam Mini 2MP and I was hoping someone might be willing to give me some pointers or clear up any apparent misconceptions I've ...
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Bug read an image from SD card and draw it on TFT
I have developed a code to read an image stored on my SD Card and display it on a TFT. I can read the image from the SD Card successfully but I cannot draw it on the TFT. I dunno where is the bug.
...
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RF24 - Split data in payloads at sender and then rebuild on receiving end
I'm trying to send some data using nRF24L01+ transceivers, but I need to use 8 byte payloads for reliability. The data I'm sending is much bigger than that, so I need to split it into 8 byte packets ...
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Serial clock for SPI
I'm trying to configure my ADC(LM98725) registers through Arduino UNO via SPI but I'm facing a small problem, it would be great if somebody help me out. I have to configure my 16 bit ADC registers ...
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Arduinino & Max7219
I'm using a MAX7219 and 6 (six) seven segment displays
I used my own board and two purchased on ebay - no difference in operation.
MOSI, and CLK are correct and verified with my scope (Tektronics)
CS (...
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Arduino stops working after some receivings from RF
I made a sketch that receives an rgb code from a remote Arduino using nrf24l01 and while it works for the first receivings then it stops working. I placed a testing Serial.println in the loop to test ...
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Arduino DUE and a ledmatrix with issues
I am trying to code something for fun using an Arduino Due and a LED matrix. The led matrix has a backpack controller. This device is using SPI. So I connect MOSI and SCLK to their respective pins and ...
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Simple question about the SPI clock for Intel Edison
I am doing a project with an Intel Edison Arduino breakout board.
http://store.arduino.cc/product/E000052
http://download.intel.com/support/edison/sb/edisonmodule_hg_331189002.pdf
I have a device ...
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Don's NDEF library and bluetooth
I am trying to connect my Android smartphone with my Arduino Uno by sending a NDEF message to my phone.
I know that the MIME type for bluetooth is application/vnd.bluetooth.ep.oob but in my PN532 ...
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What bytes do I send to the MAX7221 to light an LED (in an led Matrix)?
Datasheets
LED Matrix (p2): https://www.circuitspecialists.com/products/pdf/M105057CHR1.pdf
MAX7221: https://www.sparkfun.com/datasheets/Components/General/COM-09622-MAX7219-MAX7221.pdf
...
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How to disable RX led on Arduino Micro
I am using the RX LED pin as CS for my SPI connection and experiencing problems while debugging and communicating via SPI. Is it possible somehow to disable the RX blinking while using the serial ...
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Remap SPI functions to default pins Arduino Zero via software?
I am looking at the documentation for the Arduino Zero, and I am a little confused.
It indicates that pins 13, 12, and 11 can be used for CIPO, COPI and SCK, but using SPI.begin() puts the signals on ...
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ADS1262 and 2.2 SPI TFT (Two SPI Slave) with Arduino
I am interfacing two SPI slave module i.e. ADS1262 and 2.2 SPI TFT with the Arduino Ethernet board.
When I test each device on its own it works. Initially, I interfaced the TFT to the Arduino and it ...
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Ethernet shield and sd card not working togather on arduino mega
I am making a web-client with an Arduino mega and Ethernet Shield. I am trying to receive data from a web-server running a php script and saving that data to the SD card located in the Arduino ...
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Sparkfun canbus shield with LSM6DS33 dual SPI problem
Hello fellow arduino users! I have a question regarding using the Sparkfun Canbus shield in conjunction with the LSM6DS33 sensor on a dual SPI configuration. I have managed to get theese two to ...
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Arduino (Mega 2560) Ethernet Shield 2 (W5500) - Can't connect
I'm having issues connecting to my arduino mega via ethernet. Its a very basic start to the code just to get the network side up and running, them im going to add in what I actually want it to do. For ...
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COM disconnects and program fails when including code trying to initialize SD card (RP2040 Pi Pico W running Arduino)
I'm having an issue where anytime I run a program such as the SD card read write example (Below) the COM port disconnects. The only changes I have made to the example code is I am using SPI1 instead ...
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Fast wired communication protocols
I have an esp32 connected to an FPGA about 2 cm on a PCB. I am trying to send a constant data stream to the FPGA at a throughput of around 1.5 MB/s.
This is too fast for UART, I've been considering ...
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