All Questions
12 questions
0
votes
0
answers
100
views
Waveshare ePaper display via IT8951 hat driver for Raspberry pi 4 model B
I bought the 10.3 epaper display which I am trying drive it from a Raspberry Pi 4. The official wiki instructions (https://www.waveshare.com/wiki/10.3inch_e-Paper_HAT) is using BCM2835 which I assume ...
- 101
1
vote
0
answers
682
views
SPI Chip Select (CS) Control?
I am working with spidev on my RPi4 project and I have noticed that there is a significant delay caused by the CS signal. I am using the hardware CS pin (CE0, pin header 24) to drive the CS signal for ...
- 11
-1
votes
1
answer
68
views
spi driver works on pi 3 and pi 4, but not on pi cm4
I have a spi driver for an nrc7292. When I load it on a pi3 or 4 it works every time, but when I load it on a cm4 it only loads correctly about half the time. What could possibly be different? Once ...
- 59
2
votes
1
answer
900
views
Enable ENC28J60 on Raspberry Pi 4 SPI1 CE1
I have a Raspberry Pi model 4B V1.4 running:
Linux raspberrypi 5.10.42-v7l+ #1422 SMP Tue Jun 8 13:03:05 BST 2021
armv7l GNU/Linux
I want to connect an ENC28J60 spi ethernet adapter on spi1. Using ...
- 121
3
votes
0
answers
322
views
How to write a Kernel module using SPI properly?
I have no experience writing kernel modules. I build some examples with gpio interrupts and they worked prety well. Now I want to use SPI from my kernel module and I will explain why I need it.
I am ...
1
vote
1
answer
945
views
How is spidev and the spi-bcm2835 module related?
Removing either one deletes the SPI devices from /dev/
What's the difference between the two modules and how do they relate?
- 119
3
votes
2
answers
513
views
Single channel SPI DMA
The documentation on the SPI peripheral says:
Two DMA channels are required, one to read from and one to write to the SPI.
Is this necessarily true? I have a device where I need to write a few ...
- 181
2
votes
0
answers
553
views
Accessing 3+ SD/MMC /dev/mmcblk devices
I've successfully followed some instructions for access 2 SD cards via SPI on a Raspberry Pi 3: https://ralimtek.com/Raspberry_Pi_Secondary_SD_Card/
How do I configure it to access more than 2 SD ...
- 131
1
vote
0
answers
216
views
In simultaneous use of SPI0 and DPI Mode 3 interfaces, can SPI0 CS0 be moved to a pin other than 8?
I am attempting to design a device using a Pi Zero which needs to connect to both an ENC18J60 SPI ethernet controller, and a VGA monitor via Mode 3 DPI and the Mincepi Pi Zero pi2vga schematic. While ...
- 121
2
votes
0
answers
3k
views
How to setup resistive LCD touchscreen over SPI
I've been following a guide for setting up an LCD touchscreen, without success. When the screen is plugged into the GPIO pins it just shows a white screen. After all my attempts it remains white.
...
- 187
0
votes
0
answers
385
views
SPI problem when install CAN controller driver
I updated my raspi to 3.18.7+ last days and i also need new driver for my modules. I was waiting for PICAN board driver for pi and yesterday i uploaded it. Before uploaded;
ls -al /dev/spi*
crw-rw---...
- 61
2
votes
2
answers
13k
views
"Inappropriate ioctl for device" error since upgrading Rasbian & firmware
I was happily controlling Shiftbrite LEDs using SPI and Python based on this code
Today I upgraded my Pi using
sudo apt-get update && sudo apt-get dist-upgrade
sudo rpi-update
Now my script ...
- 183