pentchye
Posts: 2
Joined: Sun Feb 09, 2020 12:11 pm

SPI conflict between touchscreen and module?

Sun Feb 09, 2020 12:20 pm

Hi there,

I've been programming in python a small identification software that works based on a RC 522 RFID reader whose communication is actually coded in C (https://github.com/danjperron/rc522_reader) and I'm using the official raspberry touch screen as well https://www.raspberrypi.org/documentati ... e/display/

Now after a reboot everything works fine but after a while either the reader doesn't read anymore or the touch simply don't work. My guess is that there is some problem with the SPI communication.

The config file for the RC522 reader is the following:

Code: Select all

# SPI_SPEED - spi clock rate in kHz. Must be >=4 and <=125000
SPI_SPEED=5000

#User id and group id (no user root allowed)
UID=500
GID=1002

# Path for store memory dump of UltraLight tags. File will named as serial number.
NEW_TAG_PATH=/tmp/

#GPIO pin (bsm2835 gpio number!) for indiction of active tasks.
GPIO=18

[0457ce6acb3182] sudo /usr/sbin/etherwake -i wlan0 78:e3:b5:b2:6c:52 #example
#[0457ce6acb3182] whoami >>/tmp/wh
[04af674a782f82] sleep 10
Any ideas on what to do? Use another communication protocol, change the SPI parameters?

pentchye
Posts: 2
Joined: Sun Feb 09, 2020 12:11 pm

Re: SPI conflict between touchscreen and module?

Mon Feb 10, 2020 9:02 am

Nevermind, I have solved the problem. You don't need to connect the touchscreen on the GPIO ports. Besides the ribbon, only GND and 5V are connected. The problem is fixed that way.

Return to “General programming discussion”