hi everyone, ı am new member in arduino forum. ı want to work sd card with rfid card reader but sd card and rfid card reader not working together. sd card is connect true but rfid card reader isnt reading card. ı think due to two modeles' spi conflict they arent working together. how can ı overcom…

Some SD card modules will not play well with other devices on the SPI bus. The problem is with the way the level shifter on the SD module is wired. The ones that do not work well have the MISO signal running through the level shifter. That causes the MISO signal to not be released so that the oth…

[WhatsApp Image 2022-05-27 at 10.29.25 (1)] [WhatsApp Image 2022-05-27 at 10.29.25]

This video may help you. This tutorial use SD card and RFID reader together. [Time Attendance System with RFID Using Arduino ,SD card module and real time clock.]

I didn't understand what I'm supposed to do

Hello, maybe it's a little late, but I had the same problem, and looking around the forum I found that you have to put a ~330 Ohm resistor between the common MISO pin and the SD card MISO pin. Hope works for you. [20221006_092455]

To any one still finding an answer like me. 330 ohms resistor? Did not work High Low Output for CS/SS SD card module? Did not work Chinese made module that might possibly the reason why so many of these solution doesn't work? Most probably My only solution to this is using a transistor NPN tran…

First of all I must say that this solution that I will put here is definitive, BUT it is done with unconventional tools, such as an air soldering station, to remove the integrated circuit from the board, and a microscope to make the cutting and tracing work. The SPI BUS has 4 wires, three of them g…

Oh my, thats a deep knowledge. Im having the same issues... I will try to change the SD module before going into this but its quite a definitive solution. Controlling the RFID via I2c bus seems to be another option but i cant find the propper library. I hope I dont have to use your solution for hun…

The Adafruit micro SD module is wired so that the MISO signal bypasses the level shifter. [image]

SD CARD and RFID not working together / spi conflict

Projects Networking, Protocols, and Devices

groundFungus May 27, 2022, 10:08am 5

In post #11 of this thread there is a schematic of the SD module that shows the MISO line going through the level shifter.

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SD CARD and RFID not working together / spi conflict

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