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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ESP-32-C3-DEVKIT1 and MCP251863 SPI Error
I am a senior at the University of Kentucky and I am working on my senior design project. I'll skip the fluff, I am working on a PCB to connect an ESP-32-C3-DEVKIT to an MCP251863 to do CAN bus ...
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SPI DAC7800 output incorrect (bipolar mode) — UPD signal timing vs CS, Orin Nano SPI + gpiod
I’m working with a DAC7800KU on a custom board and using an NVIDIA Jetson Orin Nano as the SPI master via /dev/spidev0.0. The DAC output doesn’t match the expected voltage even though the SPI transfer ...
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FR_DISK_ERR from f_write on an STM32L432KC with SPI
I have been attempting to get f_write to work on an SD card through SPI with an STM32L432KC using Elm Chan's code as a base. The error I am getting is FR_DISK_ERR ...
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Does the RDBF flag gets set automatically after transmitting a byte?
I’m working with at32f403a. I’m trying to understand the flow of SPI communication. I’m using polling not interrupts in my implementation of an SPI_TransmitReceive ...
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Do Intersecting SPI signal return paths cause major issues or do they kind of just pass through each other like light?
ADS1299 on left. MCU input pins on right. SPI signals going between them on layer 1 Layer 2 is a ground plane 0.11mm dielectric between planes Frequency of signals is around 60MHz. 8ns rise time. DOUT ...
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Are Intel-Altera EPCS/EPCQ configuration flashes using SPI or a proprietary Active Serial interface?
In the datasheets of Intel-Altera configuration flash devices (EPCS and EPCQ series), the interface is described as Active Serial Interface (AS) rather than SPI. The interface pins (nCS, DCLK, DATA, ...
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Getting SD card to IDLE state with an STM32L432
I have been having difficulty getting an SD card to initialize to communicate over SPI. I am using a 32GB PNY Elite SD card, and the microcontroller I am using is an STM32L432KC. Below is the code I ...
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Why is my ADC (LTC2448) resetting mid conversion?
I am looking for some ideas on how to troubleshoot a funny issue I'm seeing with my LTC2448 ADC. I am using it to sample signals from a few different electrodes and feedback sources, and in the data I ...
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Corrupted display output on SSD1322 OLED using STM32 SPI
I'm using an STM32H755 with an NHD-2.7-12864WDW3 OLED that has an SSD1322 driver, running in 4-wire SPI mode. SPI communication seems to work, but the display shows a noisy area at the top and ...
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SPI track length for daisy-chained 74HC595s
I'm using the SPI peripheral of an MCU to send out serial bits to 16 daisy-chained shift register chips (74HC595). All these 595s are laid out with approximately equal spaces in between, and the ...
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Unused QSPI pins of W25Q128 flash
I've read general advice for unused pins is to tie on to some known potential (GND, 3.3V), but no where in any datasheet (of the specific IC, and similar parts from Winbond) it covers what to do with ...
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Do I need to keep a pull up resistor in SPI CS line of AD5941
I am designing a stand alone board which contains only AD5941. AD5941 contains SPI interface. STM32 board is used for communicating with AD5941. Cable assembly will go from STM32 board to SPI ...
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Can two MCUs communicate through SPI, if their supplies are from two isolated DC/DC convertors?
The situation is like this: a common voltage source of 12V is available. Two PCBs, each with its own MCU that is powered from that 12V, using its own isolated DC/DC convertors. (example of the ...
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ADF4001 Programing And Testing
I trying to program the ADF4001 in order to make a PLL with an N counter and R counter of 1, but I have no output on the CP pin. I am unsure if it's the way I am programming the chip or the layout I ...
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ADS1256: no response but device seems to be working
I'm trying to make a minimal setup with ADS1256 and blackpill (STM32F411CEU6) to work. My schematic is the following: I'm taking the 3V3 from blackpill board, the CLKIN is a PWM signal generated by ...
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