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 ...

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27 views

WiFi chip or module with schematics advice [on hold]

I'm looking for a product advice. There's a lot of products and i need to choose one and i want to ask an advice from who know different brands. I need a wifi chip with minimal connection schematics ...
1
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1answer
26 views

How to write a SPI flash

I am using the Atmel ARM M0+ MCU (ATSAMD20J18). I have written a bootload for it. The bootloader will check the first few bytes (lets call it magic key) from an external SPI flash memory to determine ...
2
votes
1answer
45 views

MicroSD card SPI with ATmega32

I want to communicate with a microSD card with an ATmega32 using SPI. I make a simple SPI loopback, and it works fine. Now, how can I communicate with the microSD card to write and read simple bytes ...
0
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1answer
41 views

Need help with communicating with card reader!

For my school project I'm using the MFRC522 card reader and an FPGA with VHDL. I'm using SPI lines but I can't understand how am I supposed create a communication with it. From what I've understand ...
0
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1answer
47 views

How to interface two wire & three wire SPI device?

ADC AD9266 Here is the datasheet of ADC AD9266. page no 25 of it is SPI I'm working on a Project where I have to interface my ADC with MCU 8051. The Problem I encountered with is my ADC supports two ...
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1answer
32 views

ideal state of SPI MOSI and MISO pins?

Just wondering , If some how the MOSI and MISO tracks which connects the slave get cut. At that time, its disconnected from the slave. So if the micro controller tries to read data from MISO pin, ...
0
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1answer
62 views

Why is the MISO not level shifted in this circuit?

I am looking at SparkFun's CC3000 breakout board schematic. CC3300 is TI's wireless module. The CC3000 operates on 3v3. And because the breakout board is intended to be used with an Arduino (which has ...
2
votes
1answer
97 views

Are all connections to my ENC28J60 required?

I'm trying to connect a ENC28J60 module that exposes a SPI interface to my Beaglebone Black. I only have pins 1 (NET_CS), 2 (SCK), 3 (MOSI, i.e., D0), 4 (MISO, i.e., D1), 5 (GND), 10 (VCC) connected ...
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2answers
79 views

How to send a buffer with spi

I use an atmega32 and I want to use the SPI bus. I have the Adafruit 24 channel, 12 bit pwm led driver. I use a buffer to set the pwm for a certain channel. The question is how to send the whole ...
0
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1answer
45 views

Bus pirate interface with with winbond chip

I have successfully interfaced to my winbond chip via the bus pirate. I have successfully executed the chip identifier command and chip erase commands via spi, i would like to read and delete the ...
0
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1answer
34 views

Interfacing MAX7219 with Bus Pirate v3.6

I am currently trying to interface a MAX7219 LED driver with a Bus Pirate 3.6 (Firmware v5.10 (r559) Bootloader v4.4). I have the following circuit breadboarded (along with some decoupling caps on ...
0
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1answer
32 views

Getting wrong data from SPI Flash SST25VF010A

I'm trying to interface an mcu (tm4c123) with external SPI flash memory SST25VF010A. I execute the Read-ID instruction, but instead of gettting BF and 49 (manufacturer and device ids) - I get BC and ...
0
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1answer
41 views

Can SPI slave work with wrong clockphase setting?

In our prototype board, we have one 16-bit SPI based ADC [ad 7798] and an SPI based switch [adg1414]. Though some other guy has written the driver for it, and its also working. However when I ...
1
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0answers
132 views

How do I transfer more than 1 byte at once via SPI bus? [migrated]

I have an AD5685R DAC that I am trying to communicate with over SPI. Per the datasheet, ...These [24] bits are transferred to the input register on the 24 falling edges of ...
1
vote
1answer
69 views

Accelerometer gyrometer for radxa board - i2c configurable addresses vs spi

I am looking for an accelerometer/gyrometer that has configurable address. It should run on a radxa rock board using i2c, or some spi solution. I am using that board (PRO) ...
5
votes
3answers
965 views

Is the SPI Interface just a protocol or actual hardware?

I want to use the SPI interface between a PIC and an ENC28J60. However, there are no pins on the PIC called MISO or MOSI that I can use for SPI. So is SPI just a protocol, which I can use with any ...
0
votes
0answers
117 views

Getting to work RFID-RC522 reader / writer with Teensy 3.1

I am trying to use the RFID-RC522 reader / writer together with a Teensy 3.1. I cannot get it to work. I always get the error: MFRC522 Software Version: 0x0 (unknown) WARNING: Communication ...
1
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0answers
77 views

Missing clock edges when using SPI on the CC430

I'm currently using the CC430F5137 and I'm having an issue with using SPI to communicate with an external flash. I'm currently using DMA to send out SPI comms using the UCSI_B module. Most of the ...
0
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0answers
38 views

Anyone familiar with TI's ADS1210

I'm trying the build a two-channel thermometer using an ATMEGA328 and two ADS1210. I've connected both ADS1210 via the common SPI lines (SCLK, MOSI, MISO) to the ATMEGA328, for DRDY and CS I'm using ...
1
vote
1answer
96 views

ATMEGA328P SPI MMC/SDIO

I want to connect an ATMEGA328P to a mobile phone, a Samsung Galaxy S3 to interface some data. I need to use the microSD port behind the battery cover for this purpose, so here is the question, Is it ...
0
votes
1answer
77 views

Wiznet Wiz820io (W5200) Module - No data on MISO Line

I had a working circuit with Wiznet W5100, but to get better performance I switched over to Wiznet W5200 (in Wiz820io module). This involved rewiring the pins, changing the register address and also ...
0
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0answers
39 views

Serial SPI EEPROM multiplex DI/DO line

Just want to make sure I didn't miss something: according to the data sheet of 25xx010 the DO pin is strictly high-impedance during addressing and writing and only driven when reading. In my ...
0
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1answer
77 views

What is the difference between 1-bit SDIO vs SPI?

What exactly is the between 1-bit SDIO vs SPI? Does one have advantages/disadvantages over the other?
0
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0answers
127 views

SPI LCD Screen on OpenWrt based hardware using Atheros AR9331

I'd like to connect a graphics lcd 240x64px to my OpenWrt based hardware, which is based on Atheros AR9331 MIPS architecture. The development board I'm using has SPI outputs... I've been using the ...
0
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0answers
58 views

Off board SPI communication over 2 meter Lenght Bus

I have few queries on my SPI interface application. Specifications: Sensor: LDC1000. Data Out: Over SPI bus, f = 4MHz. SPI Bus Length = 2 meters. Raising edge= Data out, Falling edge= Data In. I want ...
0
votes
1answer
50 views

AVR SPI slower than expected

I'm running an ATMega88A at 8MHz and have the SPI configured to run at Fosc/2 = 4MHz. In theory, shifting out 5000 bytes over SPI should take 1/4000000 * 8 * 5000 = 10ms. But according to the ...
1
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0answers
32 views

Can't drive adafruit display with Arduino DUE

I'm currently trying to write a library for the Adafruit ST7565 graphic display. (see links below) The current one is entirely AVR specific and the code is generally pretty unreadable given the ...
1
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1answer
35 views

AVR SPI2X has no effect

I've got an ATMega88A configured to run on internal 8MHz clock: lfuse = 0xE2 hfuse = 0xDF efuse = 0x01 F_CPU defined as 8000000 This in confirmed in the 'real ...
3
votes
3answers
188 views

AVR SRAM limitation

I'm just an enthusiast looking for some advice. I'd like to use a microcontroller to read frames from a camera and write those frames to a small LCD screen. The camera and screen are on the same SPI ...
1
vote
2answers
278 views

Communication between micro controllers - I2C, SPI, UART?

Basically I have two microcontrollers that I need to communicate with each other. Both controllers send and receive data. Basic idea that I have: I2C, SPI - What I think we can NOT use these ...
1
vote
1answer
59 views

SPI reading from slave

I have small question about how bytes move around during SPI reading. I have a flash memory chip and microcontroller. Suppose I want to know jedec data from the chip(although it can be any data, this ...
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2answers
71 views

Raspberry Pi and TLC5615 DAC

Currently I'm working in a project in which I need to programmatically control 2 currents from 0 to 1 Amp. My plan is to use two DACs controlled by a Raspberry Pi. My idea was to use the MCP4725 but ...
1
vote
2answers
75 views

Multiple out signals with single clock

Here is the deal.. I need to transmit data to 8 identical components. Each component has a clock and an input signal. MCU only sends data. Components only receive data. All 8 components are the ...
0
votes
1answer
88 views

SD Card Access Library

I am accessing my SD card using SPI. But I've found this to be slow and I am also sad that when there is a faster protocol already supported by my SD card I am using a slower version. Is there a C ...
1
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1answer
126 views

SPI not working, ATmega328 only sending 1 byte

I am trying to get SPI working on an ATmega328. This is my code: ...
0
votes
0answers
73 views

How long of a wire and how big of a load can I have for SPI bus?

I have a system where I will connect up to 128 identical magnometer ICs up to an FPGA. I am trying to decide between SPI and I2C for comms. If I use SPI the setup will require 128 + 3 wires IF all ...
1
vote
1answer
54 views

Cable for transmitting 4MHz 3V3 signal

I am building a device on breadboard where there are 2 ICs: a microcontroller and some auxillary IC, they should communicate via SPI with a 4 MHz clock. Because I don't have enough place on my ...
0
votes
0answers
85 views

Canon EF SPI data protocol and IS activation

I have been trying to find information about Canon EF data protocol between lens and body. So far I have seen examples how to control focus or aperture but I would like to know how IS is activated. Is ...
2
votes
2answers
208 views

Erratic ADC output

I'm using a 12 bit ADC (MAX1270), SRAM (23LC1024) and PIC18f4550 to measure temperature transient at the output of an RTD. The communication protocol is SPI. The voltage is sampled and sent to PIC, ...
1
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2answers
418 views

Porting SPI code from (Intel) Galileo to Edison - Arduino

I'm currently working to port some Arduino sketches from Intel Galileo that use SPI (using a prototype Arduino Breakout board). I haven't been able to get it to work so far - but I have used an ...
0
votes
2answers
132 views

Two different SPI modes in one microcontroller

I am interfacing two chips with SPI communication with atmega328. One chip uses SPI mode 0 and other one SPI mode 1. Is it advisable to toggle modes in micro each time interrupt request is received ...
2
votes
2answers
289 views

STM32 SPI half duplex (1-wire Bidirectional) problem

Update: see my answer for fix. I'm trying to read 4 byte from a SPI-compatible slave (MAX31855) in 1-wire bidirectonal SPI half-duplex. Here is my code [SW Controlled SS] [SO->MOSI] ...
0
votes
1answer
43 views

Connecting GPIO and SPI signals via cable

There is a requirement in one of our systems to transfer signals from one board to another board in the same system. The signals are GPIOs and SPI lines from I.MX6 processor and it is in 3.3V ...
0
votes
1answer
86 views

Hy28B display with STM32

I'm trying to get this Hy28b display work with my stm32f103 MCU. Somehow the display doesn't respond. I've found out I cannot communicate with it, my SPI setup is the following: ...
0
votes
0answers
92 views

SPI always returns null while reading

We need some help in SPI protocol. We've been using an AVR microcontroller ATMega324PA (DIP) and an ADXL344 accelerometer (QFN Breakout). Both chip operates at 1.8V and supports I2C & SPI. Lately ...
0
votes
0answers
97 views

SPI interface using pic with cc2500

Datasheet of cc2500 is here: http://www.ti.com/lit/ds/symlink/cc2500.pdf . I looked at the SPI timing diagram on page 22. I have gone through the datasheet of cc2500 and understood that. idle state ...
2
votes
1answer
113 views

SPI Interrupt Handler delay in STM32F303?

I'm working with an STM32F303 microcontroller configured in slave mode running at 72 MHz, and I've come across some strange behavior that I'm trying to track the origin of. The master first sends ...
2
votes
2answers
165 views

Writing to SD Card cheaply

So, here's the scenario: I have an Arduino and an SD card. Unfortunately, I don't have one of the fancy shields, and I don't have the time to order one. As we know, Arduinos run on 5V, and SD cards ...
0
votes
1answer
141 views

Daisy Chaining ADC Sensors

I'm creating a grid of 200+ pressure sensors and need a clean way to get their values back to the master controller without a mess of wires. To me it seems like daisy chaining all the sensors ...
1
vote
1answer
102 views

STM32F2xx: Data from SPI Slave to Master

I have a STM32F2xx connected to a FTDI UM232H using SPI, STM32F2xx will be configured as SLAVE and FTDI will be configured as MASTER My scenario is this, I am getting data in STM32F2xx, and when I ...