SPI is a low-level 3-wire serial bus interface with clock, data in and data out.
0
votes
3answers
64 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
54 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
36 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 ...
0
votes
2answers
37 views
Redefining Slave-Reset-Pin in MegaISP on ATmega2560
I want to make a Arduino ISP-Shield universal exchangeable between Arduino models. For this purpose I want to use the ISP-Header in combination with Pin 10 (like the Arduino Ethernet-Shield does). The ...
0
votes
0answers
34 views
Reading/writing garbage when programming AD45DB161D EEPROM (SPI) using Arduino
I'm trying to program the AD45DB161D. I found two libraries and Arduino example code both aren't functioning as expected. I suspect it's hardware problem.
When reading the data and dumping it to the ...
2
votes
1answer
69 views
What are some good older devices that I can scrounge i2c or spi modules from?
I am a newcomer to electronics design and I'd really like to start fiddling with making my own circuits. I have a raspberry pi which has both I2C and SPI interfaces, and I'm wondering if there's any ...
3
votes
2answers
112 views
Manual SPI interface on Raspberry PI
I am trying to control a MCP4131 digital pot from my Raspberry Pi using the
library here
Using the GPIO pins, I am "emulating" an SPI interface. I bring the ChipSelect pin to low, write my byte, ...
0
votes
0answers
71 views
SPI interfacing between FTDI and Lattice FPGA
I am trying to establish SPI interface between FTDI FT2232H and Lattice MachX02-1200ZE.
The following code for this purpose compiles successfully and the last SPI_ReadHiSpeedDevice() function returns ...
6
votes
1answer
87 views
Does an SD card in SPI mode respect chip select/slave select? Seems to be resetting in my application
I have an application where I have a microcontroller (NXP LPC1343) which is connected to an FPGA via 16-bit SPI. There is also an SD card using the same SPI port (MISO/MOSI) but with a different CS/SS ...
0
votes
1answer
62 views
How to send ASYNC 8,N,1 serial data over an SPI interface using two Arduino Uno boards
Need help with sending ASYNC data between two Arduino UNO R3 micro-controllers.
System design follows:
RS232 modem 19,200,8,N,1 --> UNO-1 D0=(rx), D1=(tx). RS232 parameters cannot be changed because ...
3
votes
0answers
50 views
SPI transaction timeout linux device driver
I am stucked for last 3 days at a point if anyone have any info regarding it then please do share...
I am working on eink device driver with msm8960 qualcomm chipset.
...
4
votes
2answers
105 views
How to deal with multiple pull-up resistors on modules
I was thinking about doing a modules for a development board I did a few days ago that will include spi/i2c interfaces.
The problem is that I didn't included pull-up resistors in the MCU pins in the ...
1
vote
1answer
43 views
Difference between SMPEND and SMPMID
I'm interfacing an SPI chip with a PIC18 device, programmed with a C program compiled with the XC8 compiler, using libraries from plib.h. In the docs, I read:
...
1
vote
1answer
30 views
Renesas RL78 SPI Baudrate Change
I am using an Renesas RL78 and SPI to communicated with an SD card. I have the driver working using the single command Baudrate of 400kBaud when sending both commands and data.
Of course, this is ...
5
votes
1answer
163 views
Serial Communication over 1 Pin?
Okay guys, I'm in a bit of a pickle here. I have the following circuit:
As you can see, pin 3 is my only output. I've actually already had this board printed, so there's not much room for ...
1
vote
3answers
84 views
Use 74LCX245 level transeiver for SPI / I2C
I'm needing to convert the levels of the SPI and I2C busses of a 5v microntroller to a 3.3v card reader and epprom memory so I choosed to use the 74LCX245 since its a bidirectional transeiver.
But ...
3
votes
1answer
129 views
SPI routing question…Maximum length SPI can be routed
Basically my question is regarding maximum length of SPI routing, and route efficiently in my scenario and any timing issues(Setup and Hold).
I am just explaining my scenario. Please bear with me, it ...
0
votes
0answers
48 views
Are there any metastability issues with microcontroller SPI slave ports that can operate during sleep?
If one is using SPI to interface two microcontrollers that may spend much of their time sleeping, and if the SPI slave port is supposed to wake up its controller when data is received, that would ...
2
votes
0answers
70 views
SPI Read returns only 0 in slave when I hook up SS to INT
I am coding a SPI slave using a PIC16F877A in CCS C and need to be aware when the SS line (pin 7) goes from high (idle) to low (active) as information from the master is framed as a stream of bytes ...
1
vote
0answers
92 views
Writing an emulator for a SPI like slave device (LED Driver PT6959) using a PIC
I am working with a legacy device that uses a "SPI like" protocol. This device acts like a:
SPI "master", but expects to talk with only one "slave" device. It
does not expect any output/data ...
4
votes
1answer
95 views
Which SPI mode to use?
I'm interfacing a 23LC1024 SPI Serial SRAM with a PIC18, using the C18 compiler and the built-in functions from <spi.h> as described in the Compiler ...
0
votes
0answers
42 views
25cl040 EEPROM and arduino, just getting 0's as output
I try to write and read a 25LC040 EEPROM with my Arduino, but I'm just getting zero's as output. I followed allong with this tutorial.
This is my code:
...
6
votes
1answer
137 views
AVR timer speedup on ATmega328
When running at clock prescaler of 64 on ATmega328, one of my timers speeds up for unknown reasons at a particular time in the execution.
I am using two timers on ATmega328 to generate the clocking ...
4
votes
4answers
167 views
ATtiny2313 refuses to be programmed after setting CPU clock to 500kHz
The other day I was writing a program for an ATtiny2313. Once it worked I decided to test it at the various clock speeds that are available and programmed through setting the LFUSE as described on ...
2
votes
1answer
137 views
How to write to 93LC46B EEPROM from an Arduino using SPI
I have a question regarding eeproms and an Arduino (I am using Arduino Uno). I have the following eeprom: 93LC46B. From the datasheet I understand that in order to write the integers ...
-2
votes
1answer
65 views
spidev_test.c analysis [closed]
I'm trying to connect a Raspberry Pi with a PIC32 through SPI. For RPi I'm using the spidev_test.c code (I'm modifying it to suit my needs) but... because I'm a novice in programming hardware, I'm ...
4
votes
0answers
99 views
Help to identify unknown Sync Serial Bus
Does somebody already seen a sync serial bus communication like that ?
Repeated Pattern :
Detail of beginning :
I fail to identify it...
it look like I2C but :
it have a clock at 2MHz (so ...
0
votes
0answers
51 views
Library for multi-master comunication of two ATTinys 261/461/861 I2C/SPI
I am building device with two ATTiny 461 connected by about 60 cm long cable. I need ATTinys to send/receive only few bytes once a time. Random time, random direction. I would like multi-master ...
2
votes
1answer
391 views
Best way to communicate Raspberry Pi and ATTiny13
What is best way to connect two or three microcontrollers, ATTiny13 to Raspberry-Pi and get master (Raspberry Pi) communication? Are there any ready libraries for ATTiny13 for SPI or I2C? Maybe some ...
3
votes
2answers
349 views
SPI.h for ATTiny
Is there a different implementation of the Arduino SPI library that can be used for the ATTinyX5 series? I assume, partly because I believe the ATTiny SPI is provided via USI... I got the environment ...
5
votes
2answers
224 views
SPI Clock on PIC unstable
I'm trying to configure the MSSP module of a PIC18F25K22 into SPI master mode. I'm looking at the timing and the clock doesn't remain steady through the whole transmission. A picture shows it better ...
2
votes
3answers
201 views
Generation of text on composite video
I'm building a homebrew computer. I want some way to get video out, preferably along the lines of 80x25 text. I'm not interested in framebuffer graphics.
Does such a thing exist as a single-chip text ...
0
votes
0answers
61 views
Can 74HC595 drive FDW9926A - Dual N-Channel 2.5V Specified PowerTrench?
Can 74HC595 drive FDW9926A - Dual N-Channel 2.5V Specified PowerTrench ?
I use
MCU -> (SPI) -> 74hc595 ->(Parallel GPIO) -> Mosfet
Is it possible?
2
votes
2answers
117 views
4 GPIO 16 Mosfets
I have 4 GPIO's and I have to drive 16 mosfets for my application.
MCU -> 4 GPIO -> something must be here(SPI mosfet driver??) -> 16 mosfets
I thought that if I have an SPI mosfet gate driver IC, ...
3
votes
1answer
139 views
Serial Peripheral Interface
I was going through an article related to SPI. There was a configuration named 'Daisy Chaining', in case of multiple slaves.
So far, what I have understood about SPI (based on wikipedia) is,
SPI ...
17
votes
3answers
422 views
What's the catch with FRAM?
After recently acquiring an MSP430 Launchpad I've been playing with various microcontroller projects. Unfortunately, the MSP430G2553 only has 512 bytes of RAM, so doing anything complex requires ...
2
votes
1answer
173 views
ATMega168 SPI tranmission will not start
Scenario
I have an ATMega168 using an external 10MHz crystal. The DIV/8 fuse bit is not set. The processor takes the outputs from 4 quadrature rotary encoders. Their rotation direction information is ...
5
votes
1answer
172 views
Occasionally the first byte of data from an SD card SPI read is bad
The device I am developing is an SD card storage add-on to a retro computer, SanDisk Ultra II 1.0 GB SD card in an SD card socket (I have no idea if the brand is significant, it just happens to ...
1
vote
3answers
216 views
controlling SPI devices using the Arduino - different voltages
My arduino board uses 5v to power the atmega chip. I was wondering is there any thing wrong with powering my atmega at 5v but say I power my MCP4922 dac at 3.3v does it matter? It just that I've seen ...
13
votes
2answers
252 views
Is SPI safe to be interrupted?
I'm writing to a microSD card from within my firmware, but it's the lowest priority task, so it can be interrupted by other tasks while it's in the middle of reading/writing.
Now suppose I ...
2
votes
3answers
166 views
Can Arduino MISO be set as output?
So I designed a PCB which consists of an atmega328 controlling a digital potentiometer (MCP4131) using SPI. I stupidly connected the pot's i/o to the MISO (master in, slave out) pin on the arduino ...
-1
votes
1answer
100 views
Interface an SPI OLED swtch with a PC
I'm making a prototype with limited engineering skills, and have the need to integrate a NKK OLED Rocker Switch (SPI interface) with a Windows PC. I've the development kit that allows me to change ...
1
vote
0answers
54 views
What's the best way to integrate SPI and MSC buses?
I have two chips. The first chip has only an SPI interface. The second chip has only an MSC (microsecond channel) interface. What's the best way to integrate them? Do you know any IC manufacturer ...
1
vote
3answers
481 views
Difference between MISO/MOSI and TxD/ RxD
What is the difference between USART and SPI ? There are [TXD/RXD] for USART and [MISO/MOSI/SCK/SS] for SPI.
I know that SPI is a synchronous protocol but USART is hardware. But, what's difference ...
1
vote
3answers
357 views
Two wire vs. three wire serial interface for RTC
I'm looking to choose an RTC for a project I have in mind.
I have the following options (linked to datasheet):
DS1307
DS1302
The main difference seems to be the communication protocol. The DS1307 ...
0
votes
0answers
213 views
STM32F4 + MCP4922 DAC + SPI + DMA = 0
I want to transmit data to MCP4922 DAC using SPI with DMA but as with most non-audio DACs it requires a pin toggle to latch data in the DAC buffers after each TX. There is a Chip select associated ...
-2
votes
1answer
125 views
Simple Implementation of the AD9834 DDS Chip [closed]
I'd like to see a simple implementation of the AD9834 DDS chip. I'd like to use this in a homebrew Amateur Radio build.
The test circuits in the datasheet were rather confusing, and the ...
-1
votes
1answer
500 views
How poorly does a bit banged spi fare as compared to the wiring pi library functions? [closed]
I have bit banged some python code to run my 12 bit ADC (MCP 3208) using my raspberry pi.
I wanted to know how slow is this going to be as compared to using the library functions of wiringpi python ...
-3
votes
1answer
65 views
Mobile phone or iPod as digital signal generator? [closed]
I have an idea to use the mobile phone audio output to use as a signal generator.
Because we could decode tones from sound, it should be possible to decode pluses from the sound too.
My question ...
2
votes
1answer
373 views
Use unused SPI MISO pin for I/O on ATTiny
I want to use an attiny85 for a project that will be controlling some LEDs over a pseudo SPI that only needs to use SCLK and MOSI. Is there any way to reconfigure pin 6 (MISO) on the 85 to be used as ...
