We’re rewarding the question askers & reputations are being recalculated! Read more.

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
0
votes
1answer
409 views

SPI communication Problem Arduino

I'm trying to set up SPI communication between two Arduinos (UNO and Mega), I want to read the status of the slave output pin from the master. I connected a diode to pin 9 of Mega and I wanted to ...
1
vote
1answer
895 views

How to connect a digital sensor through SPI

I want to connect a ADXL355 development board accelerometer to an Arduino. I cant get any data form the sensor. The data_ready pin is never high and I can't read the registers. The connections (user ...
2
votes
2answers
1k views

Can I set arbitrary SPI clock speeds?

I would like to interface an ADC (in particular this one: http://www.linear.com/product/LTC1400) with an Arduino Nano via SPI. The specified max clock speed for the ADC is 6.4 MHz. The Nano can do up ...
2
votes
2answers
176 views

Arduino based SPI programming of LT1257 not working

I am trying to talk to an LT1257 using an Arduino Nano Atmega328. I am not using the default slave select pin. I am using pin 5 as chip select for the DAC. The LT1257 data sheet shows this timing ...
0
votes
0answers
512 views

Reading values from Wiznet w5500 chip over SPI

I am trying to get the MAC address that is stored on the Wiznet w5500 chip. On page 29 - click here, it has the address of the values. It state that "This block can be selected by the BSB[4:0] value ...
2
votes
1answer
5k 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
vote
0answers
2k views

Load website from SD card

I combined two different codes together, a captive portal and a SD card web server. I encountered a problem which the website in the SD card doesn't load when I connect to the AP (captive portal page)....
0
votes
2answers
226 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
votes
1answer
343 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?
1
vote
1answer
1k 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
votes
1answer
958 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. ...
1
vote
2answers
2k 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 ...
2
votes
1answer
482 views

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 ...
-1
votes
3answers
1k 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 ...
1
vote
0answers
785 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 ...
1
vote
3answers
11k 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
votes
2answers
3k 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
2k 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 ...
-1
votes
2answers
216 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 ...
3
votes
4answers
257 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: ...
1
vote
2answers
506 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
votes
2answers
5k 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 ...
0
votes
1answer
385 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
votes
1answer
224 views

Understanding Nikon modified version of SPI

I am trying to use this library to connect a Nikon lens to an Arduino. https://lainy.github.io/NikonLens/classlain_1_1t_nikon_lens.html I'm finding it very hard to understand the correct wiring. ...
0
votes
1answer
385 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 ...
0
votes
1answer
483 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 ...
1
vote
2answers
1k 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
385 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
votes
1answer
150 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
vote
1answer
128 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
923 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
294 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
417 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
110 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
votes
1answer
902 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
707 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
votes
0answers
722 views

Arduino UNO with NRF24l01 + touch screen [closed]

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. ...
1
vote
0answers
441 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 ...
1
vote
0answers
81 views

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. ...
2
votes
1answer
369 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 ...
3
votes
1answer
261 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
201 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; /*...
2
votes
0answers
1k views

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 ...
2
votes
2answers
1k 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
256 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
vote
2answers
982 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
2k 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
votes
0answers
275 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
105 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 ...
12
votes
3answers
22k 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 ...