diff --git a/zpu/umtrx/spi_flash_read.c b/zpu/umtrx/spi_flash_read.c
index 44f7b77a..aca94e01 100644
--- a/zpu/umtrx/spi_flash_read.c
+++ b/zpu/umtrx/spi_flash_read.c
@@ -43,7 +43,7 @@ size_t spi_flash_log2_memory_size(void)
     }
     if (_spi_flash_log2_memory_size < 22 ||
         _spi_flash_log2_memory_size > 24 ){
-        printf("\nWrong flash size: %d Achtung!\n", _spi_flash_log2_memory_size);
+        printf("\nWrong flash size: %d Achtung!\n", (int)_spi_flash_log2_memory_size);
         abort();
     }
     return _spi_flash_log2_memory_size;