diff --git a/sim/src/c.rs b/sim/src/c.rs
index a770ca6..dd98c19 100644
--- a/sim/src/c.rs
+++ b/sim/src/c.rs
@@ -3,11 +3,14 @@
 use area::AreaDesc;
 use flash::Flash;
 use libc;
+use api;
 
 /// Invoke the bootloader on this flash device.
 pub fn boot_go(flash: &mut Flash, areadesc: &AreaDesc) -> i32 {
-    unsafe { raw::invoke_boot_go(flash as *mut _ as *mut libc::c_void,
-                                 &areadesc.get_c() as *const _) as i32 }
+    unsafe { api::set_flash(flash) };
+    let result = unsafe { raw::invoke_boot_go(&areadesc.get_c() as *const _) as i32 };
+    unsafe { api::clear_flash(); };
+    result
 }
 
 /// Setter/getter for the flash counter.  This isn't thread safe.
@@ -49,7 +52,7 @@
         // This generates a warning about `CAreaDesc` not being foreign safe.  There doesn't appear to
         // be any way to get rid of this warning.  See https://github.com/rust-lang/rust/issues/34798
         // for information and tracking.
-        pub fn invoke_boot_go(flash: *mut libc::c_void, areadesc: *const CAreaDesc) -> libc::c_int;
+        pub fn invoke_boot_go(areadesc: *const CAreaDesc) -> libc::c_int;
         pub static mut flash_counter: libc::c_int;
 
         pub static mut sim_flash_align: u8;