diff --git a/tools/env/fw_env.config b/tools/env/fw_env.config
index 9d3b1a4..90e499d 100644
--- a/tools/env/fw_env.config
+++ b/tools/env/fw_env.config
@@ -17,3 +17,6 @@
 
 # NAND example
 #/dev/mtd0		0x4000		0x4000		0x20000			2
+
+# Block device example
+#/dev/mmcblk0		0xc0000		0x20000