Unknown issue with spi and wip


i’m doing a project where i included an sd card , everything works fine , i can read / write the sd memory
until i start the GPRS bearer , after that my spi reads only 255…

does anyone knows or have an ideea…what happens when i open the bearer that interrupts my spi communication ?

thank you…


Power supply or RF noise?


Yes, that’d be the first things to look at…