diff --git a/macros/src/trans.rs b/macros/src/trans.rs
index b50c73df29..20e3aa0a7c 100644
--- a/macros/src/trans.rs
+++ b/macros/src/trans.rs
@@ -181,6 +181,7 @@ fn idle(app: &App, ownerships: &Ownerships, main: &mut Vec<Tokens>, root: &mut V
                             &#_static,
                             #ceiling,
                             #device::NVIC_PRIO_BITS,
+                            #device::CPU,
                             t,
                             f,
                         )
@@ -196,6 +197,7 @@ fn idle(app: &App, ownerships: &Ownerships, main: &mut Vec<Tokens>, root: &mut V
                             &mut #_static,
                             #ceiling,
                             #device::NVIC_PRIO_BITS,
+                            #device::CPU,
                             t,
                             f,
                         )
@@ -499,6 +501,7 @@ fn tasks(app: &App, ownerships: &Ownerships, root: &mut Vec<Tokens>) {
                                     &#_static,
                                     #ceiling,
                                     #device::NVIC_PRIO_BITS,
+                                    #device::CPU,
                                     t,
                                     f,
                                 )
@@ -514,6 +517,7 @@ fn tasks(app: &App, ownerships: &Ownerships, root: &mut Vec<Tokens>) {
                                     &mut #_static,
                                     #ceiling,
                                     #device::NVIC_PRIO_BITS,
+                                    #device::CPU,
                                     t,
                                     f,
                                 )
diff --git a/src/lib.rs b/src/lib.rs
index be670490e7..dfb2060623 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -74,6 +74,7 @@
 //! [rtfm]: http://www.diva-portal.org/smash/get/diva2:1005680/FULLTEXT01.pdf
 #![deny(missing_docs)]
 #![deny(warnings)]
+#![feature(asm)]
 #![feature(proc_macro)]
 #![no_std]
 
@@ -119,6 +120,7 @@ pub unsafe fn claim<T, R, F>(
     data: T,
     ceiling: u8,
     _nvic_prio_bits: u8,
+    _cpu: &str,
     t: &mut Threshold,
     f: F,
 ) -> R
@@ -132,6 +134,7 @@ where
 
             #[cfg(not(armv6m))]
             () => {
+                let is_cm7 = _cpu == "CM7";
                 let max_priority = 1 << _nvic_prio_bits;
 
                 if ceiling == max_priority {
@@ -139,9 +142,21 @@ where
                 } else {
                     let old = basepri::read();
                     let hw = (max_priority - ceiling) << (8 - _nvic_prio_bits);
-                    basepri::write(hw);
+                    if is_cm7 {
+                        asm!("cpsid i
+                              msr BASEPRI, $0
+                              cpsie i" :: "r"(hw) : "memory" : "volatile");
+                    } else {
+                        basepri::write(hw);
+                    }
                     let ret = f(data, &mut Threshold::new(ceiling));
-                    basepri::write(old);
+                    if is_cm7 {
+                        asm!("cpsid i
+                              msr BASEPRI, $0
+                              cpsie i" :: "r"(old) : "memory" : "volatile");
+                    } else {
+                        basepri::write(old);
+                    }
                     ret
                 }
             }