Questions tagged [spi]
SPI is a low-level 3 or 4 wire serial bus interface with clock (SCLK), data in (MISO) and data out (MOSI). The fourth wire is a Slave Select to uniquely select a device on the bus. This signal is usually active-low. Slave Select, Chip Select, CS#, SS# stand for the same function, typically. Be sure to check the datasheet, though. The SPI bus is a *de facto* standard lacking the formal specification.
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EMC-EFT problem with TFT display Common mode Choke and TVS diodes [closed]
Before taking this job, I had never been in a laboratory and did not know these topics. Moreover, when the chief engineer left work, all the testing was left to me.
We are performing emc eft test for ...
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Connect ADS1298 to PC via USB
I designed an ECG board based on ADS1298 and schematics in this document (pages 52, 53, 55) with some customizations. I should connect it to PC via USB.
As I found here, TI evaluation board uses a DSP ...
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Digital potentiometer X9C104P with a Raspberry Pi 5 [migrated]
I've tried using a Raspberry Pi 5 to control a digital potentiometer X9C104P. I followed this wiring diagram:
Potentiometer (POT) - Raspberry Pi
INC: GPIO20
UD: GPIO21
Vh: 5V
Vss: GND
Vcc: 5V
CS: ...
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Which pins are used for I2C and SPI in ESP32-S3?
I am using ESP32-S3-WROOM-1-N16R2 Controller in my design. I want to connect Sensor with this module which has both I2C and SPI Communication pins. I gone through the datasheet for controller, but i ...
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Excessive use of vias
I am designing a four-layer board, with the layers as follows: Signal - Ground - Power - Signal. The microcontroller I will be using is an ESP32-S3, which I believe delivers an SPI-frequency of 80 MHz....
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How to reduce on-resistance and parasitic capacitance effects of my MUX setup?
I am designing a mux board to mux a flashing setup. Both UART and SPI lines are on 1.8V logic. The Mux chips have ~4-8ohms on-resistance and 1.7pF on-capacitance. Few questions:
Would I need buffers ...
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Is there any way to get a smaller SPI clock speed specifically to only one SPI slave?
I have 3 modules connected by SPI through an ATMEGA328P MCU as shown in the circuit and I have some doubts over the clock speed of the bus.
I have a 8Mhz clock on the MCU which I am assuming sets the ...
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SPI goes low too fast; Raspberry Pi Pico PIO and ADS7042
I am trying to use an ADS7042 (12-bit ADC) with my Raspberry Pi Pico with the Pico's PIO, but the signal goes low too fast and it seems to have problems going high sometimes, do I need to add some ...
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Interfacing ADC12138 with Digital Discovery using SPI
I am trying to interface ADC12138 ADC over SPI channel to Digital Discovery to read the single ended analog voltage in the rang of 0-4V on channel 2.
As described in datasheet section 1.0
Snapshot ...
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TM4C123 SPI slave reads only one byte
I'm sending the following sequence to an SPI slave in a Tiva TM4C123GXL board:
I have captured this directly from the MCU pins. Notice SCK is running at ~190 kHz (pretty slow).
The problem is that my ...
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SPI: Write to display while reading multiple blocks from SD card
I'm reading BMP images with hundreds of kB's raw from an SD card and parse/write the image data to a TFT LCD with an AVR MCU with 2kB RAM.
Reading a single block of 512 bytes with CMD17, passing it to ...
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Multiple Page Write of Flash
My querry is, I am trying to write data from a file stored in by Raspberry PI to an external flash. The size of the file is greater than 256 bytes. As Flash allows writing a max of only 256 bytes in 1 ...
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How to correctly shift the wipers of MCP4331 per SPI?
I am using an STM32 F401RE to control a Quad 7-bit digital potentiometer MCP 4331 using SPI Mode 0,0 protocol. You can find the datasheet Here. I can see that the microcontroller sends the correct ...
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Why is MOSI pulled low during communication?
I am using Allwinner A40i (ARM V7) as SPI master and STM32 as SPI slave. When not communicating with STM32 for SPI, it is correct to use an oscilloscope to capture ...
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Frequency limit for routing <32MHz digital signals adjacent to one another on different layers, 4 layer PCB
I'm running an 3.3V SPI device with an SPI clock frequency rated up to 10 MHz, with some additional digital outputs/inputs to/from a microcontroller that is clocked at 32 MHz.
Due to some space ...
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When using SPI interfaced SD Card Reader with MCU, the MCU is the master, right?
Hopefully this is a yes / no question. I just want to verify that when I'm using a simple MCU with a simple SPI interfaced SD card reader and writer, the MCU is in master mode and the SD card reader / ...
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STM32 SPI DMA issue
I have two MCU, STM32H755ZIT6 as Master TRANSMIT ONLY and STM32F103C8T6 as Slave RECEIVE ONLY.
The Master MCU is sending 18 bytes all the time via DMA and the Slave device is receiving it also with ...
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SPI slave is sending one byte twice at a very specific time in data packet and causes corruption of the whole data packet
I am trying to communicate with a display device (master) which sends two type of data packets with 50 kHz clock. One data packet is 16 bytes and one is 32 bytes long. The data format is as follows:
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MCP4151 unresponsive to commands on ESP with CircuitPython
I am trying to control an MCP4151-103E digital potentiometer from an ESP32-Devkit-v1 running CircuitPython 8.2.7.
For this task, I have the following code. This has been adapted from this Github ...
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Issue with MAX3140 UART when sending 64-bit frame using 16-bit frame configuration
I am facing an issue with the MAX3140 UART when attempting to send a 64-bit frame through a 16-bit frame configuration. The MAX3140 uses a 16-bit frame for communication, where the upper 8 bits are ...
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SPI and word length
When receiving data via SPI communication, is there any constraints for word length (bit size)?
I have a chip that sends 16 bits of data A and 16 bits of data B through a single pin, can I configure ...
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SPI2 on the bluepill STM32F103C8 doesn't work
For a while, I have been trying to interface a 1.8 TFT ST7735 to my STM32F103C8 bluepill using SPI2 and HAL.
I tried SPI1 and has worked perfectly, but because I am interfacing LoRa to the bluepill ...
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Unable to communicate with SPI based display board
I need to communicate with a display board that is acting as master and my board will act as slave.
The reference document says that
"
Totally 26 bytes for communication between display and ...
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AD7708 ADC SPI receive problem in STM32
I'm currently working on a ADC AD7708. There is not much document or library for this IC. I'm writing ad7708 driver for stm32f446 mcu. In datasheet register structure of ad7708 shown as below:
I ...
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Can WINC1500 be used with SPI for connecting to a router?
I'm planning to buy the WINC1500 WiFi module. I have heard that it contains a SPI layer, which can be used for telling the WINC1500 to connect to a router.
But as I can see in the documentation, I ...
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LTC4332 communication issues
I have a slight issue with the communication between my Arduino Uno R3 board and an LTC4332 SPI extender chip. The Arduino is the master and the LTC4332 device is the slave.
The Arduino SPI channels (...
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Noise in SPI Chip Select when communicating between boards
I'm writing SPI code to communicate between an STM32 Nucleo Board and a TI Dev Board, the CC1310-90. I'm using a manually toggled chip select pin.
The data my TI board is receiving is junk, and after ...
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ESP32-S3 SPI pins?
I am a beginner in electronics and tried to use ESP32-S3 for interfacing RFID and unable to find SPI pins in the the data-sheets. Tried Googling for pin reference but after reading so many blogs and ...
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ESP32 SPI issue (voltage levels)
I have (technically had because it smoked while trying to resolve this issue) a PCB board with an ESP32-WROOM-32 Dev Board plugged in. I had 4 external ADCs (AD7680ARJZ-REEL7). ADC 1 and 2 were on ...
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Arduino SPI and analog pin management
I am using Adafruit Feather M4 Express to read buttons, switches, encoders and potentiometers and control some LEDs of a control panel. I am running into issues with the pin management.
I have 5 ...
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How to read data from a 6DOF sensor by SPI?
I am new to firmware programing.
I have a 6 DOF sensor module and want to connect to a ESP12F development board to read data. Please see below picture for my 6 DOF sensor module.
Here are my current ...
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AD677JNZ Raspberry Pi Connection
Relatively new to electronics, I would like to connect the AD677JNZ analog-to-digital (ADC) to a Raspberry Pi 4 to monitor the voltage of a potentiometer. However, I am having issues with the ...
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Can't write to status register of SST25VF010A flash memory
I'm having trouble writing to the status register of a SST25VF010A-33-4I-SAE 1Mbit SPI flash memory on a board I recently made. I'm using an STM32F401CBU6 to communicate with the memory.
I can read ...
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ESP32 VSPI/HSPI SPI channels only support 3 slave devices?
From what I understand there are two methods for multi-subnode SPI - Regular Method and Daisy Chain Mode [1]. In the regular method, each slave device is designated a separate CS (chip select) pin on ...
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Reading BMI270 IMU data with STM32F4 MCU
I have a flight controller with a GYRO in it. The BMI270 is connected to SPI 1, and using STM32CubeIDE for the build, I am trying to read sensor data and send it via UART.
CHIP_ID = 0x24 is the value ...
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Can SD card readers read a card which only implements the SPI mode?
I've read How can I initialize/use SD cards with SPI?.
If I connected a microcontroller's SPI slave pins to an SD card shaped connector, would this allow the microcontroller to appear as a very small ...
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Can't get SH1106 1.3 oled to work (SPI)
It's my first project this big - an arduino (Pro Micro) based midi controller. After all the research, schematics and pcb designing I got to assembly and wanted to try out the display, but then I can'...
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Turning power on to relays interferes with thermocouple reader
I have 6 3V reed relays SIL03-1A72-71D that connect to a raspberry pi pico directly via gpio pins 11, 12, 13, 14, 15, 18, and 19 on a custom pcb. The connections to the relays are: 1 is connected to ...
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Can I implement QSPI (quad SPI) communication using an MCU that only supports ordinary SPI
This question is most probably about pin-configurations registers.
I mean since QSPI is the same as SPI with more data bus-width (correct me if I'm wrong on this first assumption), then doesn't it ...
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Communication between two microcontrollers with independent Vcc powers
I need to send signals from one STM32 to another, while each has its own power source (each a separate battery pack). both units operate with the same voltage level (3.3 V) but @ different core clock (...
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SPI protocol master CS pulled low
If I run the system on SPI protocol and keep the master slave connected with it, will communication happen if I disconnect both the CS pins master and slave and tie them to ground?
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SD card stuck writing single block of data
I noticed a very strange behaviour on some of my micro SD cards.
I have a project that writes data to files stored on my SD card (FAT32 formatted) via the SPI interface of a PIC32 microcontroller.
...
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HAL_SPI_TransmitReceive not working properly
I am trying to use HAL function to drive SPI to read analog voltage from external ADC (adc128s102). I see what I expect to see in first 16 CLK with MISO(Blue) and MOSI(Yellow) line. But what's causing ...
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PL230 DMA & PL022 SPI transmit only 9 bytes
I am trying to implement SPI+DMA on W7500. The chip has a PL230 DMA and PL022 SPI (with 8 level FIFOs). First I just want to transmit N bytes using DMA basic mode. On the pins I only see 9 bytes (or ...
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I2C with MPU6050 and STM32F407stuck at send address status check
I have the following code for an accelerometer sensor, MPU6050.
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Slave SPI not firing interrupt
I have 2 STM32F407 discovery boards for which I'm trying to setup a multi slave SPI bus. The first slave is working but the other one is making problems once I connect the second CLK input onto the ...
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Managing Multiple SPI Slave Devices with I2C for Slave Selection
I'm working on a project where I have one master device and 64 slave devices. I'm facing a challenge with the SPI protocol's limitation in terms of the number of Slave Select (SS) lines needed for ...
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SPI read of MAX31856 in Verilog
I am trying to read the K-type thermocouple temperature with MAX31856 in Verilog.
Configured the configuration registers CR0 & CR1.
The conversion result is stored in the registers 0xC, 0XD, 0XE. ...
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ESP32-WROOM-32E Custom PCB Failure to send LoRa Packet
I am having troubles trying to send a LoRa packet to a receiver. In the serial monitor I am stuck in the while loop and it keeps printing dots. Below is my code and I will attach a photo of the eagle ...
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Wired network for a lot of ESP8266 / ESP8285
I found this project at GitHub, and I would like to do the same but add a few improvements.
Rotate modules, according to this radiation pattern:
Would it work better?
As I understand ESP8266 doesn’...