diff --git a/lib/flash_internal.c b/lib/flash_internal.c
index 3d27a3d..167dc4e 100644
--- a/lib/flash_internal.c
+++ b/lib/flash_internal.c
@@ -138,11 +138,12 @@ int32_t flash_internal_write(uint32_t address, const uint8_t *buffer, size_t siz
 		for (uint32_t i = 0; i < size && (address + i) < (page_start + page_size); i += 2) { // verify if no bit needs to be flipped to 1 again
 			if (*(uint16_t*)(buffer + i) != (*(uint16_t*)(address + i))) { // verify if the data to be written is identical to the one already written
 				identical = false;
-			}
-			if ((*(uint16_t*)(buffer + i) & *(uint16_t*)(address + i)) != *(uint16_t*)(buffer + i)) { // check if a bit needs to be flipped from 0 back to 1 (through an erase)
-				erase = true;
-				identical = false; // should already have been set, but I want to be sure
-				break; // no need to check further
+				// in theory writing flash is only about flipping (individual) bits from 1 (erase state) to 0
+				// in practice the micro-controller won't allow to flip individual bits if the whole half-word is erased (set to 0xffff)
+				if (*(uint16_t*)(address + i) != 0xffff) { // flash is not erased
+					erase = true; // we need to erase it for it to be written
+					break; // no need to check further
+				}
 			}
 		}
 		if (identical) { // no data needs to be changed