USB host shield issue


I just got the USB host shield from sparkfun (

When I tried to execute the board test sample I got the following error :

Error: OSCOKIRQ failed to assert

Circuits At Home 2010 USB Host Shield QC test routine

Press any key to continue¦ Reading REVISION register…Die revision invalid. Value returned: 00 Test FAILED! Test Halted. 0×55 pattern is being transmitted via SPI to aid in troubleshooting Press RESET to restart test

I'am using USB Host library downloaded from (with the name

I tried to change MAXGPX and MAXRESET to #define MAXGPX 7 #define MAXRESET 8 but problem still persists.

I use an ATMEGA 2560 linked to my PC and an external +9V power supply. (SPI pins are correctly connected according to atmega2560 specification)

I found the solution,

In the Max3421e_constants.h header file just redefine MAX_SS on line 22:

#define MAX_SS    53

After that all tests passed successfully :)