--- Quote Start ---
But I face a problem of defining a 128bit type< how can I solve this?
Thanks
--- Quote End ---
Probably the best way is to use an array of some defined types. For example:
int32_t My128bitArray[4];
int16_t My128bitArray[8];
int8_t My128bitArray[16];
By the way you should choose the type your array on the basis of what you have to do with it. If you have to write 32bit registers BadOmen gives you the answer:
http://www.alteraforum.com/forum/showthread.php?t=44527 If you have to send 1 byte on a SPI you should go with an 8 bit array etc etc..
What are you supposed to do with a 128 bit var ? If we can know..