convet NSData to Byte*

 NSString *myString = @"WorkList"; //Assuming your string is here

        NSData *stringData = [myString dataUsingEncoding:NSASCIIStringEncoding]; //This is the NSData representation of the string

        NSInteger len = [myString length];

        Byte *bytes = (Byte*)malloc(len);

        memcpy(bytes, [stringData bytes], len);

        for(int i=0; i<[myString length]; i++){

            NSLog(@"byte[%d] is %d",i,bytes[i]);

        }