SPI is a low-level 3-wire serial bus interface with clock, data in and data out.
2
votes
2answers
60 views
SPI and clock active low or high
I am trying to get SPI working on an MCU. The SCK on the MCU is labelled \$\overline{SCK}\$ which means it active low but my device has no overline on the SCK. Can I use the same clock. If not what ...
1
vote
1answer
38 views
chip select on one to one spi connection
I connect an imx233 (master) and atmega168a (slave) through SPI. I am trying to debug the communication. I have problem with imx233's chip select, therefore I connect CS of the AVR onto the ground. ...
1
vote
1answer
94 views
Why I cannot see SPI signal properly with oscilloscope?
When I monitor a SPI bus with only one probe, I see such output when data is transferred.
I know that I need to use a logic analyzer to monitor the SPI, but I wonder why I see such signal that ...
3
votes
1answer
45 views
Which interface is better for my OLED displayer?
I have a 0.96 inch 128x64 Yellow-Blue oled display module like this: OLED module and i want to use of it. The Driver is SSD1306. When you see in the SSD1306's datasheet you know it support 8-bit ...
0
votes
1answer
59 views
Design review: SPI, ISP and multiple slaves
I am designing a small breakout board for an AVR ATmega8U2, which will allow me to learn about the AVRs, SPI, ISP and USB. In this process, I came across something I'm wondering a bit about: How to ...
2
votes
2answers
75 views
SPI multiple slave termination
I've been reading about signal integrity and went through this site reading about it as well as other references. Alot of the topics deal with a single slave, but not so much multiple slaves.
I'll be ...
1
vote
2answers
57 views
Can I program a QUAD SPI Chip with a standard SPI microcontroller?
I have to program a MX25L12835 Quad SPI chip. This is a Quad SPI serial flash. Is it possible to program this using an arduino? Can this be used as a simple 1 channel SPI or can quad SPI interface ...
1
vote
1answer
67 views
Why SPI Master mode frequency is half of bus frequency?
I was reading about SPI here On Slide 2, It says,
Maximum Master mode frequency = bus frequency/2
Maximum Slave Mode frequency = bus frequency.
My obvious question was Why?
P.S. This document is ...
3
votes
1answer
135 views
Can SPI programmer interfere with other components on same pins?
I'm building custom made Arduino board, with SPI header.
SPI pins on Atmega328 are 13,12,11 Arduino pins which I use in my project already.
Can other components conected on these ports interfer with ...
0
votes
0answers
45 views
How do I program a serial EEPROM IC using a raspberry Pi?
I am trying to program the 25L12835F Serial EEPROM with the firmware of the Pineapple WiFi router. I have the u-boot.bin file from Alfa. I have tried a programmer from eBay, but the software is unable ...
0
votes
1answer
71 views
Is it possible to change Roving rn-171 WiFly module device configuration through SPI and not UART?
I am interfacing rn-171 WiFly module with PIC18F27J13 chip.
I want to save both USARTs available on the PIC for other purposes.
I am wondering whether I can just connect the Roving SPI pins to the ...
0
votes
0answers
40 views
MCF51JE SPI NOR Flash
I am working on an application that requires a NOR SPI flash unit from Micron(N25Q). What I am trying to figure out is how to address the device from a MCF51JE micro from Freescale.
As I understand ...
1
vote
2answers
117 views
How to code SPI Slaves?
This is a normal sequence for an SPI Read:
I want to code for an SPI slave. How is this normally done? How can the slave respond so quick (in the next bit!) with the appropriate data out after it ...
5
votes
1answer
217 views
How can I buffer SPI?
I have a board with a device that outputs data over SPI (as slave device) and a microcontroller. The device signals that data is available (24 bits) by setting a certain pin low, around 8000 times ...
2
votes
3answers
130 views
I²C, SPI, CAN protocoles and OSI model
could you please refer me to a reference or explain me if I²C, and SPI ** are just **Physical layer protocols in OSI model (i know that this model is for communication and maybe not exactly for ...
1
vote
1answer
62 views
spi interrupt code
I am trying to let two uC talk to each other. Both chips are from dsPIC33EP family. The slave will respond according to what master has sent to it. My question is, since SPI is full-duplex, would it ...
0
votes
0answers
49 views
N-FET vs. NPN Transistor for 3v3 Logic
I'm looking at the datasheet for the MLX90333 3-axis hall effect sensor. Section 16.4 (pg 40) shows the schematic for connecting the device to a microcontroller. The MLX90333 uses a 3-wire variant of ...
1
vote
1answer
42 views
Clocks setup when programming Atmel via ISP?
When programming an Atmel microchip over SPI (ISP), what external clocking do I have to provide to programee? Does it have to match programmer's internal clock frequency, or can be totally different ...
0
votes
1answer
56 views
USB to SPI line level converter
I have a quite powerful DSO, MSO2024 from Tektronix with SPI interpreter on board.
Any idea to convert USB line levels to SPI so I can watch them with this scope?
2
votes
1answer
100 views
Issue controlling MAX7301 GPIO Expander via SPI using Arduino Uno R3
I'm trying to write a driver to control a MAX7301 GPIO port expander that will be controlled via SPI.
I've used SPI before and it's pretty simple, but I've been working on this for a few days and I ...
4
votes
2answers
86 views
lpc1788 reading via SPI from enc28j60
I have a problem with SPI communication with enc chip. Basically i cant use SSP (in SPI mode) as it is, because enc expects CS to be low for multiple bytes while SSP shifts it high after each byte ...
1
vote
1answer
85 views
USB Control of WS2801 LEDs
I have a string of WS2801 LEDs (the type most often used with an Arduino or Raspberry Pi over SPI), as well as an evaluation kit/breakout board for USB-to-SPI-master (MCP2210).
However, I am more of ...
3
votes
4answers
315 views
PCB Signal Bus design
I have a pcb with a SPI bus with several sensors that have to be connected to this bus. Since 90 degree traces are not recommended in a proper PCB design I ask myself how to connect so many sensors ...
1
vote
1answer
60 views
SPI Interfacing using Serial Port or USB
I have a nRF24L01+ module from Nordic Semiconductors. It has SPI interface. My laptop has USB ports and I have a Serial Port (Using a USB-to-Serial_Port adapter). What is the best possible solution to ...
4
votes
4answers
143 views
What are some design concerns for off board SPI communication?
Overview:
I am communicating among 3 custom pcb boards with dspic33's on them using SPI. I have a master and 2 slaves, but I am sending both the slaves the same data (and letting them choose what to ...
3
votes
2answers
72 views
How can I wait for a response from an SPI slave with an ATmega16?
I'm trying to connect to a slave in SPI net, I need to send a command and receive a response. I've used the below code for connection:
...
0
votes
1answer
73 views
Interfacing with an LCD screen
I have managed to salvage the LCD screen from an old Tom-Tom (the model number of the screen is LTE430WQ-F0B-0BS). It comes with a driver for the screen on the back, but it doesn't look humanly ...
3
votes
2answers
157 views
SPI device prevents ISP programming
I have an ATmega8 with a Nokia LCD 5510 connected to it. Everything works great on a breadboard and my next step is to move it to a more permanent board. My problem is that I can't program the ATmega8 ...
1
vote
1answer
463 views
Getting started with BeagleBone and SPI
I want to add additional network interfaces to my BeagleBone Black. I would like to use an Ethernet module I found, EM2803_SCH, and want to figure out how to configure the pins on my BeagleBone's ...
8
votes
2answers
189 views
Why does my waveform start ahead of the trigger?
I am learning how to analyze SPI bus clock and data using an entry-level digital storage oscilloscope. I'm using a BK Precision 2542B to measure the output of the clock and MOSI lines from a Netduino ...
3
votes
3answers
188 views
Do I need SS for SPI single-slave communication?
I'm using Atmega328 as a master in SPI communication with a single slave. Is there a way to avoid using the SS (slave select) pin for SPI? That pin can also be used for PWM output, which I would like ...
0
votes
1answer
201 views
What are some inexpensive easy to use SPI devices I can experiment with? [closed]
Introduction
I'm completely new to EE, but have decades of software development experience. I want to learn to interface with multiple SPI devices on a single SPI interface on a Raspberry Pi. I'd ...
0
votes
2answers
125 views
Send more than one value via SPI/arduino, MAX5483, 10-bit digi-poti
With help from efox29 I worked out to control the MAX5483, 10-bit digital potentiometer (data sheet here) with an arduino using SPI. Now how can I trigger more than one value?
I tried to do that with ...
1
vote
1answer
141 views
MAX5483, 10-bit digital potentiometer controlled via SPI by arduino
I am desperately trying to get to work an arduino program to control the 10-bit digital potentiometer MAX5483 with SPI, but something is not working. I get some resistance values, but the protocol is ...
0
votes
1answer
208 views
STM32 I2S Interupt Usage
I was trying out a sound experiment, starting off with sample code which sent data to the Discovery F4's audio codec using I2S. The sample code used polling in the main loop and sent data when the ...
0
votes
0answers
57 views
CC2540-Honeywell SPI
I am now working with Honeywell HSCMRRN100MDSA3 pressure sensors, I want to establish a connection with TI CC2540 Bluetooth LE SoC, in SPI mode. Which ports of the TI SmartRF05EB Evaluation Board rev ...
0
votes
0answers
213 views
Raspberry Pi with SPI RFID reader/writer
I've been using Arduino for years and am now transforming to take a sip on the Raspberry Pi. I've been using the MF522 13.56 MHz RFID reader in my Arduino projects. It uses an SPI interface to ...
1
vote
1answer
84 views
How do I configure a external RTC that uses 3-wire SPI for the LPC 2387?
Here is the link to the datasheet of the RTC PT7C4302.
I can do it with MISO, MOSI, but SISO I have no idea how to do. Some similar code examples would be great.
0
votes
0answers
167 views
Raspberry Pi SPI and AtMega
I'm trying to make multiple DMX modules that communicate with a raspberry pi through SPI, I would assume SPI would be the fastest ?
The modules are made of an atmega (not sure which, but probably ...
0
votes
0answers
105 views
AXDL345 Accelerometer on SPI Raspberry PI with bcm2835
I have this accelerometer ADXL345. I am trying to read data from it from SPI using the BCM2835 Library here.
When I run this, I SOMETIMES get a value back (other than zero), but it's never ...
0
votes
2answers
248 views
Interfacing a MCP23S17 (SPI) with a FPGA
I am working with a MCP23S17 SPI I/O expander chip in a VHDL project on my Basys 2.
At first glance I thought this was just a simple SPI interface where I put the chip select low and it will give me ...
1
vote
1answer
126 views
How to get 10bit data of ADC using SPI protocol
I am doing Single master multiple slave implementation.
Master - PIC18F4550
Slave - PIC18F4520
A potentiometer is connected to the Slave. Slave will convert the Potentiometer value to digital and ...
-5
votes
1answer
119 views
How much max distance of SPI & USB & I2C and TWI(without any IC [closed]
How much max distance of SPI & USB & I2C and TWI(without any IC(my mean is directly)), and how can i amplify these?
-4
votes
2answers
291 views
Can i directly connect this chip to PC and how can i amplify it (NRF24L01)? [closed]
Can i directly connect this chip to PC and how can i amplify it for increased range (NRF24L01)?
for more: http://www.semiconductorstore.com/cart/pc/viewPrd.asp?idproduct=765
3
votes
4answers
118 views
N-Ch FET with open-drain output
I stumbled across this line in this datasheet (page 10):
Serial Data Output Pin. Internal N-Ch FET with open-drain output that
requires external pull-up resistor. It shifts out the previous ...
0
votes
1answer
207 views
Help required performing Single Master - Multiple(upto 16) Slave SPI Communication using MSP430
I am planning to use MSP430F6638 for SPI Communication between a single MSP430 Master and multiple MSP430 Slaves. I am using a 4x16 Multiplexer before each Slave for providing the Chip Select Signal. ...
20
votes
5answers
1k views
Is there a difference between using a built in SPI module and bit-banging?
Is there a difference between the two, or is it just a matter of abstraction? My intuition says there's no difference but I'd love to be wrong.
0
votes
3answers
160 views
Synchronizing SPI ports for higher data rate
I am designing a new board which uses the NXP LPC4330 (Cortex M4 microcontroller) with a XESS Xula2 FPGA development board. In this design, the Xula 2 has limited I/O pins since it is designed to fit ...
2
votes
1answer
171 views
should I use 2 SPI devices on Arduino UNO/PRO or 2 I2C devices?
I am using a microSD breakout board and the accelerometer ADXL345 https://www.sparkfun.com/products/9836.
each one alone works perfectly fine, but once I put both (sharing pins 11,12,13, but with ...
3
votes
1answer
49 views
SD Comms Resetting Processor
I have implemented an SD/FAT combination on a Renesas RL78/G13 processor. The SD card is being driven using SPI.
The code has been proven to work on two custom target boards using a 2GB card - the SD ...
