diff --git a/zephyr/src/hal_flash.c b/zephyr/src/hal_flash.c
new file mode 100644
index 0000000..a3700bc
--- /dev/null
+++ b/zephyr/src/hal_flash.c
@@ -0,0 +1,37 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include <zephyr.h>
+#include <misc/printk.h>
+
+#include "hal/hal_flash.h"
+
+#if defined(CONFIG_BOARD_FRDM_K64F)
+#define FLASH_ALIGN 8
+#elif defined(CONFIG_BOARD_96B_CARBON)
+#define FLASH_ALIGN 1
+#else
+#error "Board is currently not supported by bootloader"
+#endif
+
+/* All of the currently supported devices allow single byte writes. */
+uint8_t hal_flash_align(uint8_t flash_id)
+{
+	return FLASH_ALIGN;
+}