diff --git a/sim/src/area.rs b/sim/src/area.rs
index 9bb7d57..c74f664 100644
--- a/sim/src/area.rs
+++ b/sim/src/area.rs
@@ -79,6 +79,29 @@
         });
     }
 
+    // Add a simple slot to the image.  This ignores the device layout, and just adds the area as a
+    // single unit.  It assumes that the image lines up with image boundaries.  This tests
+    // configurations where the partition table uses larger sectors than the underlying flash
+    // device.
+    pub fn add_simple_image(&mut self, base: usize, len: usize, id: FlashId) {
+        let area = vec![FlashArea {
+            flash_id: id,
+            device_id: 42,
+            pad16: 0,
+            off: base as u32,
+            size: len as u32,
+        }];
+
+        self.areas.push(area);
+        self.whole.push(FlashArea {
+            flash_id: id,
+            device_id: 42,
+            pad16: 0,
+            off: base as u32,
+            size: len as u32,
+        });
+    }
+
     pub fn get_c(&self) -> CAreaDesc {
         let mut areas: CAreaDesc = Default::default();
 
diff --git a/sim/src/main.rs b/sim/src/main.rs
index 5691ac2..33b2c0c 100644
--- a/sim/src/main.rs
+++ b/sim/src/main.rs
@@ -50,7 +50,7 @@
 }
 
 #[derive(Debug, RustcDecodable)]
-enum DeviceName { Stm32f4, K64f }
+enum DeviceName { Stm32f4, K64f, K64fBig }
 
 #[derive(Debug)]
 struct AlignArg(u8);
@@ -102,6 +102,17 @@
             areadesc.add_image(0x060000, 0x001000, FlashId::ImageScratch);
             (flash, areadesc)
         }
+        Some(DeviceName::K64fBig) => {
+            // Simulating an STM style flash on top of an NXP style flash.  Underlying flash device
+            // uses small sectors, but we tell the bootloader they are large.
+            let flash = Flash::new(vec![4096; 128]);
+
+            let mut areadesc = AreaDesc::new(&flash);
+            areadesc.add_simple_image(0x020000, 0x020000, FlashId::Image0);
+            areadesc.add_simple_image(0x040000, 0x020000, FlashId::Image1);
+            areadesc.add_simple_image(0x060000, 0x020000, FlashId::ImageScratch);
+            (flash, areadesc)
+        }
     };
 
     // println!("Areas: {:#?}", areadesc.get_c());