Skip to main content

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.

Filter by
Sorted by
Tagged with
-1 votes
0 answers
36 views

Why do I get the error dtostrf and ltoa not declared in the scope? [closed]

I get the two errors below when verifying the code, please review and provide suggestions / correct the code. 'dtostrf' was not declared in this scope dtostrf(pressure, 5, 1, buffer) 'ltoa' was not ...
0 votes
0 answers
42 views

Data constant and always zero from the ADXL345 accelerometer with ESP32 using SPI

I am trying to get data from an ADXL345 accelerometer using an ESP32 via SPI communication. I have configured my code following the ADXL345_WE library specifications and have verified the hardware ...
1 vote
2 answers
2k views

Rfid reader and SD card shield won't work together

I recently encountered a problem that's been bugging me for days. I want to make a project using a RFID reader and log data on an SD card with an Arduino Nano, but apparently no matter what I do, I ...
1 vote
0 answers
92 views

Issue with multiple RC522s connected to Arduino Uno

THIS IS NOT A DUPLICATE QUESTION. My main problem is that whenever I attach the third RC522, the whole system becomes unstable. When I attach the fourth, suddenly one or two of the modules stop ...
4 votes
2 answers
2k views

How to make an Arduino act reliably as an SPI slave?

I want two Arduino Nanos to communicate with each other using SPI, ideally at around 2MHz or faster. I have two standard Nanos running at 16MHz on 5V. The master uses SPI.transfer() to send an array ...
1 vote
0 answers
58 views

Deciphering AD7730 outputs

I am currently working with a AD7730 chip for analog-digital conversion. The chip is programmable, and I have been pulling code from GitHub as well as other links. I am unfamiliar with SPI (the ...
0 votes
2 answers
308 views

USART, SPI or Bit-Bang for the continuous transfer of bytes without inserted extra bits

I have heard that The SPI hardware introduces a 9th, HIGH bit between bytes USART still uses start and stop bits when in synchronous mode Are both these statements true? Can I modify the built-in ...
1 vote
1 answer
682 views

How to connect a NRF24L01 to a Wemos D1 R2

I have troubles to connect a NRF24L01 transceiver to a Wemos D1 R2 board. I succeeded on an Arduino Uno. Does anyone know the pinout? I used (same as with Uno): D13 - SCK D12 - MI D11 - MO D8 and D9 ...
-1 votes
1 answer
231 views

SPI with DMA in a Arduino Due

I have a project where I need to store data (~16 Mo) on a memory and be able to fetch the data fast (<36000 bits/s) with DMA because I have other signals to take care of. Currently I use an SD card ...
3 votes
2 answers
529 views

Send data through SPI with DMA

I need to send data as fast as possible from an Arduino DUE to an extern DAC. To do so I use DMA & SPI and I want DMA to fetch data from the memory and send it to the SPI which will just relay it ...
0 votes
1 answer
586 views

Using Arduino to Record analog signals with SPI ADC + Sampling Rate Issue

I am using Arduino UNO to Read 8-channel, 24-bits resolution Analog signals using ADS1299 Analog-fornt-end. ADS1299 use SPI interface to talk with Arduino. Currently, I can record the analog signal ...
3 votes
2 answers
1k views

Using the Broadcom AFBR-S50 with Arduino

I'm trying to interface with a Broadcom AFBR-S50MV85G ToF sensor over SPI using an Arduino, which is complicated by the fact that the provided library and reference application is written for Cortex ...
2 votes
2 answers
474 views

ESP32 SPI Mutual Communication

I have two ESP32 cards. I want to set one of these cards as Master and the other as Slave and communicate via SPI. I have done this before on Arduino Uno, but I cannot do this on ESP32. Below are my ...
5 votes
1 answer
11k views

Wrong documentation for Mega2560 SPI Pins?

This page https://store.arduino.cc/usa/mega-2560-r3 contains an image under the Documentation section which shows digital pins 10 to 13 with labels SS, MOSI, MISO, and SCK. EDIT: The documentation ...
5 votes
0 answers
339 views

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 ...
3 votes
2 answers
12k views

I2C and SPI at the same time?

I would like to ask a question relating to the following communication setup: STM32 -- Arduino Pro Mini -- ADNS3080 sensor The interface between STM32 -- Arduino is I2C and the interface between ...
2 votes
2 answers
172 views

Can I use SPI-related pins as a Digital Output?

I am trying to use an esp32 (NodeMCU-32s) as a ringlight controller for my camera. All it should do is sense when an input pin goes low (the camera's output connects to ground when the shutter goes ...
1 vote
0 answers
23 views

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 ...
0 votes
1 answer
153 views

FreeRTOS is not solving my problem to run tasks parallelly

I'm pretty new to esp32 and I'm trying to combine two codes in one, they are simple codes from projects that I found online, the first one uses PIR sensor to send message to telegram each time motion ...
0 votes
1 answer
268 views

ESP32 TTGO T-Call connect to SX1276

I have an ESP32 TTGO T-Call and I want to add a LoRa SX1276. I am new to that and I am trying to write a simple program that, when it receives a packet from a LoRa sender, sends via gsm an HTTP ...
2 votes
2 answers
974 views

How to connect two LED strips (APA102/SK9822) to Arduino UNO?

So what I am trying to do is to connect two SK9822 LED strips to Arduino UNO. I am a bit confused about how to properly set this up so I can individualy control any led. So obviously 5V should go to ...
1 vote
2 answers
42 views

Can Arduino UNO/MEGA master assert SPI SS LOW on multiple slaves at once if Full Duplex is unnecessary?

I have a computer talking serially to an UNO SPI Master and, beyond it, multiple MEGA Slaves. The slaves never talk back to the master. I understand it is normal and correct to assert SS LOW to ...
2 votes
1 answer
2k views

SCLK pulses not seen when using SPI on ESP32

I am using the following code in my esp32 using Arduino IDE for spi communication which is an example code - #include <SPI.h> static const int spiClk = 1000000; // 1 MHz //...
1 vote
0 answers
267 views

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 ...
1 vote
1 answer
2k views

Using SPI on Pi Pico, Arduino IDE

Beginner with the Pi Pico here, but I studied electronics engineering and am reasonably hardware literate. I've used mbed online for a project prior to covid. I want to use SPI to connect to a display ...
0 votes
1 answer
743 views

Arduino Bluepill STM32 spi doesn't work

Has anyone successfully use SPI1 of those pins? SCLK -> PB3 SDIO -> PB5 SDO -> PB4 MISO CS -> PA15 I've tried to use another side of SPI1 pins on the other sides of the board (PA4, 5, ...
0 votes
2 answers
874 views

SD Card Mount Failed with Waveshare ESP32 using Arduino IDE

I'm currently working on a project using an ESP32 (the Waveshare ESP32 Driver Board), and I am trying to read data from an SD card, but consistently getting a "SD Card Mount Failed" error. I ...
2 votes
1 answer
245 views

Is it possible to synchronize two SPI busses to send data out in parallel on the same clock signal?

We're working with these very odd driver chips which are sort of like shift registers except rather than latch the data at the end, the latch needs to happen over the last 'n' clock cycles in parallel ...
2 votes
0 answers
83 views

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 ...
2 votes
0 answers
186 views

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 ...
1 vote
0 answers
80 views

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 ...
-1 votes
2 answers
700 views

TFT display shows black stripes

I'm new to the field: I'm trying to drive a TFT ST7735S display (this is the model I'm currently using: https://www.amazon.it/dp/B078JBBPXK/ref=pe_24968671_487022601_TE_SCE_dp_1) with an Arduino Mega ...
1 vote
1 answer
117 views

Programming barebones ATMega328 with external programmer and no bootloader

I have created a circuit with a barebones ATMega328. I also have an external programmer (Sparkfun's Pocket AVR Programmer)... Now I want to program a particular sketch... When uploading a sketch, do i ...
1 vote
0 answers
252 views

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 ...
2 votes
2 answers
222 views

Changing SPI ports on an Arduino

My end goal is to read information from an nRF24l01 module connected to my Arduino UNO R3, and generate an interrupt whenever a message is sent to the Arduino. Now, I have read that for Hardware ...
2 votes
1 answer
169 views

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 ...
1 vote
0 answers
116 views

How to set OTA on ESP 32

I am currently using an evalkit Nina W106-00B board that incorporates an ESP32. I am desperately trying to implement OTA (Over-The-Air) updates. I started by modifying my partitions.csv file, which ...
1 vote
1 answer
704 views

25Q128 flash and garbage data over SPI

I have a logic analyzer coming in the mail, but thought I might ask for help here first. I soldered the 25Q128 flash onto an adapter and wired it up to an Arduino UNO clone as you can see in the ...
1 vote
0 answers
71 views

How to create 2 individual daisy chains using the MAX7219 Module and Mega2560

I am using MAX7219 8 digit 7 segment displays with Arduino Mega2560. Now, I have to physically space out the displays far from each other. Hence, after a certain distance the displays on the far end ...
67 votes
2 answers
226k views

How do you use SPI on an Arduino?

With reference to the Arduino Uno, Mega2560, Leonardo and similar boards: How does SPI work? How fast is SPI? How do I connect between a master and a slave? How do I make an SPI slave? Please note: ...
1 vote
1 answer
711 views

Correct usage of SPI with ISR

My Arduino needs to do: Run ISR as many times as possible/ as fast as possible. Occasionally receive data over I2C. Output data over SPI in ISR. My question is regarding SPI and ISR. The ...
3 votes
0 answers
221 views

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 ...
1 vote
1 answer
405 views

AD7768-1 library " Arduino "

I am working on a project and I need an AD7768-1 library to make this analog-digital-converter talk to my Arduino using SPI. " The AD7768-1" doesn't exist in Arduino's library. Thanks in ...
1 vote
0 answers
76 views

How to save the current SPI settings with out have a global variable keeping track?

I am making a function for one of my devices, my device needs a particular SPI setting. I was hoping to save the current setting of the SPI class into some variable, load in the required setting, do a ...
2 votes
0 answers
200 views

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 ...
1 vote
0 answers
172 views

Error with Mega2560 via SPI

I tried the following code to communicate via SPI with MPU9250 and Mega2560 But I got the following error: Error initializing communication with IMU Why I got this error? /* * Brian R Taylor * brian....
1 vote
0 answers
126 views

UART SERCOM on Pins 11-13 Arduino M0 (SAMD21)

I am a newb at coding. Does anyone have any code laying around or some time to write some to send data over UART SERCOM on pins 11/12/13 on a SAMD21 board like the Arduino M0? I am trying to send a ...
0 votes
1 answer
664 views

SPI: problems communicating with sensor using Arduino

I have a sensor which I am trying to communicate with over SPI using an Arduino UNO. It is my first time using SPI and I'm experiencing some problems which I'm hoping are just due to some ...
3 votes
3 answers
7k views

Are there any detail examples of Si4463

Recently, I bought two Si4463 chips, but I don't know how to use them. It seems complex. I'd like to know if there are any examples of an Si4463 used with an Arduino?
0 votes
0 answers
617 views

Arduino Due as Triggered DMA SPI Slave is possible?

Is it possible for arduino Due to act as DMA-SPI-slave device which can exchange SPI data (uint16_t TX[10] and RX[10]) in triggered slave mode? I have a setup in which time period is very short (~...

1
2 3 4 5
10