ChangeLog:

- big commit.

tests/mem_test/mem_test.c

@@ -16,6 +16,8 @@
  *  5. Free the block, show the free-page count again.
  */
 
+uint32_t buff[256];
+
 static void show_mem(const char *label)
 {
     uint16_t total, free_pages;
@@ -28,6 +30,13 @@ int main(void)
 {
     puts("Sprinter page allocator demo");
     puts("");
+    
+    memset(buff, 0, sizeof(buff));
+    // printf("mem_io_ports_test() = 0x%02X\n", mem_io_ports_test());
+    printf("buff size (sizeof) = %u\n", sizeof(buff));
+    printf("buff size one element (sizeof) = %u\n", sizeof(buff[0]));
+    printf("buff first element = %u\n", buff[0]);
+    printf("buff last element = %u\n", buff[(sizeof(buff) / sizeof(buff[0])) - 1]);
 
     show_mem("before:");