diff --git a/src/ethosu_device.c b/src/ethosu_device.c
index c7cded9..e8d067f 100644
--- a/src/ethosu_device.c
+++ b/src/ethosu_device.c
@@ -567,7 +567,7 @@
     assert(dev->base_address != 0);
     assert(address % 4 == 0);
 
-    volatile uint32_t *reg = dev->base_address + address;
+    volatile uint32_t *reg = (volatile uint32_t *)(dev->base_address + address);
     return *reg;
 #else
     UNUSED(dev);
@@ -583,7 +583,7 @@
     assert(dev->base_address != 0);
     assert(address % 4 == 0);
 
-    volatile uint32_t *reg = dev->base_address + address;
+    volatile uint32_t *reg = (volatile uint32_t *)(dev->base_address + address);
     *reg                   = value;
 #else
     UNUSED(dev);