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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35 views

Arduino Nano nRF24L01+ DFPlayer Mini SPI Problem

I'm working with an Arduino Nano board clone (CH340) on wireless control of DFPlayer Mini, transceiver sending a Struct variable with MachinePrefix (just in case), sound type (I have more folders by ...
1
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0answers
28 views

Load website from SD card

I combined two different codes together, a captive portal and a SD card webserver. I encountered a problem which the website in the SD card doesn't load when I connect to the AP (captive portal page). ...
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2answers
22 views

Using 8-bit instead of 16-bit in Adafruit library

I tried to modify the Adafruit_GFX and Adafruit_ST7735 libraries to make the color variable( as shown in code below) to use 8-bit instead of 16-bit for displaying 8-bit color on LCD screen. void ...
0
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1answer
31 views

Does anyone know how to connect 2 digipots to Arduino? (MCP4141)

I'm struggling with getting the code right. I'm trying to connect 2 digipots (MCP 4141) to Arduino to work separately over SPI. Has anyone got any experience with that?
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1answer
25 views

Writing to a SPI memory

Recently I salvaged a BIOS chip (EN25QH16) which has 2 Megabytes of memory (8192 pages, 256 bytes/page). I followed this instructables and it works. I double checked the opcodes because the code is ...
0
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1answer
12 views

SPIRead value changes as Wire.begin() is called - Looking for a solution

I'm working on a project where I want to send results of sensordata (Gyroscope/Accelerometer MPU6050) over LoRa. Currently I got the code written to read the sensor and create a 'code' I want to send ...
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0answers
34 views

Disable SCK temporarily to save power

for logging of environmental data, I am using a MicroSD card adapter (no brand name, eBay, China) and a 4GB Intenso SD card. I want to read data and write it to the SD card once every 10 minutes. ...
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2answers
42 views

How to use multiple SPI slaves in MKR1000 if it doesn't have Slave Select (SS/CS) pin?

I'm using a Genuino MKR1000 and I want to use the SPI interface, which I've seen that there is no Slave Select (SS)/Chip Select(CS) pin usage. How can I use the SPI interface with multiple slaves ...
0
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1answer
62 views

Realtime Stereo audio streaming over wifi

I have been thinking of setting up a realtime wireless(read Wifi) stereo audio streaming using Arduino Due or Teensy3.2 board, so that i can hear what my TV plays even in the kitchen :P (I'd refrain ...
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2answers
32 views

Arduino Problem with using SoftwareSerial and SPI

I am using an external ADC (via SPI) and also a GPS receiver (Software Serial). I tried each one of them and it's working fine. Now, when I try to integrate both of them in one sketch, I can only make ...
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0answers
57 views

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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0answers
18 views

When connecting more than one RFID to the same Arduino, is it possible to determine from which RFID the Arduino is reading?

I'm working on a project in which I need to connect two RFIDs to an Arduino Uno. Each RFID has a different function, and both are connected to the SPI bus. RFID Type is MFRC522. For both RFIDs to ...
0
votes
3answers
55 views

How do I send a string from an Arduino Slave using SPI?

I have an Arduino Uno acting as a master with 3 Arduino Nano's acting as a slaves. Looking at this example: http://www.gammon.com.au/forum/?id=10892, it tells me how to send a string from the master ...
0
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2answers
49 views

How to flash an ATmega directly without a dedicated flashing device?

An ATmega microcontroller can be flashed by a C compiler and a USB dedicated device (ISP). I tried to flash the program into the microcontroller by saving the machine code to a MicroSD card that I ...
0
votes
1answer
123 views

ArduCam ESP8266 and (Not-Mini) OV2640 Camera Module interface?

I bought ArduCam ESP8266 and a OV2640 Module. However it is not the mini-version. At the time it didn't seem like it was necessary. I might have made a big mistake here. The board has 8 female pins ...
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2answers
35 views

which spi mode shall i use given this timing diagram

I need some help to ensure my understanding of how this is supposed to work. I want to know given the attached serial timing diagram which spi mode should I use? Based on my newly found knowledge I ...
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0answers
46 views

Problem with SPI transactions on Arduino Due

I'm having problems with SPI transactions on Arudino DUE. Here are some facts about my project: ADC interrupts on pins 20 and 21 Uses SPI to read measured value Starts a new measure cycle which will ...
4
votes
4answers
76 views

Creating variable inside if statement (conditional signed vs unsigned int)

I have an SPI chip that I would like to read out with an Arduino. Some of the registers are signed int others are unsigned int. I am writing a function to read any register. A simplified version: ...
0
votes
1answer
27 views

Arduino add two spi slaves that has no slave select pin

I am working on a project where Arduino is communicating with two devices using SPI. Unfortunately, these two devices has no ss(slave select) pin to communicate with each one separately. How Can I ...
3
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2answers
127 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 ...
-1
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1answer
32 views

SPI conflict with two shields - IOREF?

Update: I've refactored the code to be very resilient to boards missing or not being able to talk to them. Then I tinkered with a bunch of pins and learned that it all comes down to the IOREF pin ...
0
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1answer
19 views

Understanding Nikon modified version of SPI

I am trying to use this library to connect a Nikon lens to a ardunio. https://lainy.github.io/NikonLens/classlain_1_1t_nikon_lens.html Im finding it very hard to understand the correct wiring. ...
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0answers
15 views

How to make a 433 scanner by SI4463? [duplicate]

I want to make a 433 scanner like this . But , I just know how to use RH_RF24.h to control SI4463. Although there is a function about RSSI in RH_RH24.h . But it is not suitable for scanner . So ,I ...
0
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1answer
56 views

Does receiving data with SPI stop the main loop?

I have a loop of code running on a Mega 2560 that is running at a certain speed, which I get from an Arduino Uno. I have tried to talk with I2C but when I receive the data from I2C, the whole code ...
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1answer
41 views

Using SPI Interrupt causes two servos to lose functionality

My Arduino MEGA clone (ATMEGA 2650) reads SPI data as a slave using an interrupt. There are also two servos that make an arm (shoulder and elbow). When I comment out the line that attaches the SPI ...
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1answer
71 views

How do I use the Arduino Mega as a 16-bit SPI slave?

I have to interface an Arduino Mega as a slave with a SPI master running at 1 MHz SCK. The master will send and ask for two bytes in a single transaction. I tried using the following code for the Mega....
0
votes
1answer
59 views

Arduino bug when “myFile = SD.open” is inside loop()

My Arduino resets / bugs each time I put myFile = SD.open in loop(). In setup() it works fine. I have a 20*4 LCD and an RTC connected to I2C, an SD card reader connected to SPI, and a fingerprint ...
0
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1answer
39 views

SPI Overflow in 328 slave with i2c sensor

I am working on creating sensor poller that is going to be polling multiple sensors and then, on request, provides its data to the master. The master polls the slave (SPI) at 50hz and the slave is ...
1
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1answer
35 views

WaveHC Library Trouble

I posted this on the main Arduino forum, but no one has responded in 24 hours. I'm trying to use the WaveHC library from Adafruit with a custom PCB. I am having trouble getting the SPI com to work ...
6
votes
2answers
119 views

Using SPI without driving MISO

I am developing an application where an Arduino Pro Mini communicates with a 12-bit ADC over SPI. The communication is one-way, meaning that the ADC will only send data back to the Arduino, not ...
0
votes
2answers
21 views

Atmega boot loading UART or SPI

I have an Atmega 328 chip and want to load the Arduino boot loader to the chip. I have planned to use a SPI protocol to do this, but I have read other posts saying that they have done similar using an ...
0
votes
1answer
37 views

NRF24L01+ unable to receive data

I have 2 Arduino UNO R3 nodes communicating using NRF24L01+ transceivers with the TMRh20 library. Setup I have original as well as cheaper but 'compatible' arduinos. One of the nodes uses an original ...
0
votes
1answer
37 views

Explanantion of Addressing

I'm new Arduino user and I'm trying out a SPI protocol to interface a SRAM, specifically, the 23LCV512. I have found the instructables steps to interface a SRAM using the SPI bus on an Arduino UNO ...
0
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0answers
47 views

Talking to ADS8698 (18-bit ADC) over SPI

I want to talk to an ADS8698 over SPI (see page 36 for details on their SPI implementation) using a Teensy 3.2. Right now I'm only getting zeros back and I feel like (perhaps wrongly) that I've ...
0
votes
2answers
49 views

Arduino nano & pro micro SPI simple communication

I'm working with Arduino boards with AVR C coding to perform simple SPI communication from master for simple blink application on slave side. They don't work, the TX function on the master side doesn'...
4
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0answers
116 views

Arduino UNO with NRF24l01 + touch screen

I have an Arduino UNO, a NRF24L01 as receiver (receive data from elsewhere), and this touch screen from Adafruit for display and control. The Adafruit TFT is a shield so it fits the UNO perfectly. ...
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0answers
51 views

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 ...
2
votes
0answers
58 views

Connecting Saleae Logic 8 to MISO (pin 12) on Uno 3 w/ NRF24L01+ halts program

I have an NRF24L01+ with the base module (regulates voltage) connected to an Arduino Uno 3. I'm using the tmrh20 NRF24 library and am running one of the example programs. I'm trying to sniff the SPI ...
2
votes
1answer
48 views

Attempt stacking 'CAN-BUS' and 'USB Host' Shields on Mega 2560

I've run into a case of 'In theory it works, but in reality'.... I'm using the CAN-BUS Shield V1.2 from Seeed studio. Many things are written in broken english, so I'm starting to wonder if I can ...
1
vote
1answer
45 views

While condition with & bitwise of PINx read

I was looking into ATmega32u4 datasheet to configure the SPI, and there is initialization snippet for data transmission. void SPI_MasterTransmit(char cData) { /* Start transmission */ SPDR = cData; /*...
1
vote
2answers
155 views

Unable to interface AD7705 (SPI) with Arduino

Code as shown below. I am unable to get the 16-bit data. Can someone help me identify my mistake? byte spiTransfer(volatile byte data) { SPDR = data; while (!(SPSR & _BV(SPIF))); return ...
0
votes
1answer
45 views

Arduino SPI Communication with H3LIS100DL accelerometer

I'm having trouble getting information off the accelerometer I'm trying to use. What code should I use to read the X,Y, and Z axis? I've read the data sheet but I don't have any experience with SPI ...
1
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2answers
164 views

Controlling a capacitive touch screen that doesn't have I2C/SPI

I have been searching for cheap slim 3" 16:9 capacitive touch screens for a while now. But I couldn't find any that had an I2C or SPI interface. The cheap displays always have these ribbon cables with ...
0
votes
1answer
149 views

Reading an MCP23S17 I/O expander port with the Arduino SPI library

I am trying to read an MCP23S17 I/O expander port B with the Arduino SPI library. The following example is simple as possible, and I still can not get it to work. The setup is an MCP23S17 I/O ...
0
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0answers
48 views

Arduino Due SPI will not loop

Help please I am trying to connect an Arduino Due via a SPI bus to a MAXIM31855 thermocouple sensing chip. I am using Arduino IDE version 1.6.11. The problem I am having is that the code will only ...
0
votes
1answer
36 views

Can MP3 be sent to SPI of Adafruit Music Maker Arduino shield instead of from its SD card?

Can uncompressed MP3 audio data be sent from Arduino board, by SPI, to Adafruit Music Maker shield instead of from the SD card on the Music Maker? Instead of using SD card on Music Maker board, I ...
3
votes
2answers
989 views

How to increase SD card write speed in arduino

I'm creating a data-logger system which logs data in SD card at a high speed of about 20000-30000 bytes per second. But the SD library in arduino currently writes data at about 4500-5000 bytes per ...
1
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2answers
56 views

Delaying pushbutton input to microcontroller while it's busy processing I/O

I am trying to create my own home automation using Arduino. I am using shift register for reading input(via push buttons) and writing output to led's. I am using SPI interface to communicate with ...
0
votes
1answer
137 views

SPI MCP23S08 to arduino strange stop/start behaviour

I have built an Arduino minimal breadboard circuit to test some parts I recently bought and I successfully managed to get the I2C MCP23008 working perfectly with LEDs and an LCD display. However I ...
0
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1answer
77 views

Can I read/write to MX25L8006E flash memory using Arduino?

Is it possible? I read this but as I'm a total noob on electronics (I'm mainly into programming in C and asm) I want to hear your opinion anyway. I have Arduino UNO with a breadboard and a bunch of ...