All Questions
91
questions
1
vote
0
answers
48
views
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 ...
- 551
0
votes
1
answer
42
views
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 ...
- 1,324
2
votes
1
answer
154
views
E-Ink with Atmega and avr-libc
I am trying to understand how to drive an E-Ink display like the Adafruit 4196 with i.e. an Atmega328 with avr-libc.
From what I could learn so far, I would write the image/text to a frame buffer and ...
- 551
1
vote
1
answer
51
views
Could an AVR ISP connector be reused to add SPI-Interfaced memories without programing the controller?
I have no previous experience designing AVR-Compatible hardware.
I have a board which uses an ATMega 2560 and has a SPI bus which is already used by a SD adapter. After some datasheet reading, I ...
- 183
0
votes
1
answer
113
views
How does the ATMega32 know that the incoming SPI data signals are the program to be burnt?
From my understanding, in order to burn a C program to the ATMega32's flash memory, the program is first compiled and converted into a hex file which is then uploaded using a computer program such as ...
0
votes
0
answers
93
views
SPI interfacing a sensor doesn't seem to work
I'm trying to get a feeling for how the SPI protocol works. I built this cirucit using Proteus simulator.
simulate this circuit – Schematic created using CircuitLab
And then according to the ...
- 137
0
votes
1
answer
121
views
Read MicroSD card with USB reader while it is connected to (powered-off) microcontroller
I have created a small breakout board, where a microSD card is inserted and I can access its signals.
Now, when the necessary SD signals are connected to an AVR microcontroller via SPI, they ...
- 391
0
votes
1
answer
497
views
Confused about MAX6675 thermocouple sensor SPI protocol
I'm using an AVR microcontroller to take readings from a MAX6675 (SPI K-type thermocouple ADC chip).
I am having difficulty understanding what is required by this chip's SPI interface. The datasheet (...
- 249
2
votes
1
answer
155
views
Configuring the Ports of an AVR Microcontroller for SPI Use
I am trying to configure the an ATtiny84A for use with SPI, but I have some confusion with what Is being said in the datasheet for configuring the ports. The ATtiny84A has, what the datasheet calls, &...
- 245
1
vote
0
answers
199
views
ATmega328P presumably dead after probable SPI short circuit
I am trying to use an ATmega328P to interface an SPI device (RFM95W radio module). This worked pretty well (I could measure the correct signals on SCK, MISO, MOSI and CS), but after some programming ...
0
votes
1
answer
368
views
Issue with avr spi slave interrupt in proteus ATmega8
I want to get some data from spi, but spi interrupt doesnt work. I get a message and a pause in proteus instead of a signal on LCD. How to fix this?
My code:
...
- 1
0
votes
0
answers
83
views
SPI MOSI line only hits 1.2V for speeds above 500kHz and below 4MHz (3.3V logic)
I'm trying to drive a ST7789 TFT display (datasheet) with an ATTiny-416, but for some reason SPI fails at speeds above 500kHz. So far I've had these results:
500kHz: pass
666kHz: fail
1MHz: fail
...
- 400
0
votes
1
answer
53
views
MCP40821 DAC not responding to AVR
I'm trying to interface with an MCP40821 using SPI from an AVR. Using these pin maps:
...
- 435
2
votes
2
answers
249
views
Getting started with AVR programming concepts
I am trying to get started with programming the AVR. I have chosen to use Atmega328P (which is in my Arduino Uno). When I did web search regarding the initial steps for learning the AVR programming, I ...
- 1,079
0
votes
1
answer
77
views
.96 inch TFT with ST7753 and AVR - can't draw individual pixels
I bought this from aliexpress: https://www.aliexpress.com/item/32859042892.html It seems to be a good display, even a bit higher res, than advertised, however, I'm having trouble doing anything more ...
- 75