diff --git a/services/ticktimer-server/src/lib.rs b/services/ticktimer-server/src/lib.rs
index ad9f3ac01..cba2a0685 100644
--- a/services/ticktimer-server/src/lib.rs
+++ b/services/ticktimer-server/src/lib.rs
@@ -19,11 +19,9 @@ impl Ticktimer {
     /// note special case for elapsed_ms() is "infalliable". it really should never fail so get rid of the Error
     pub fn elapsed_ms(&self) -> u64 {
         let response = send_message(self.conn,
-            xous::Message::BlockingScalar(xous::ScalarMessage {
-                id: api::Opcode::ElapsedMs.to_usize().unwrap(),
-                arg1: 0, arg2: 0, arg3: 0, arg4: 0
-            })
-        ).expect("Ticktimer: failure to send message to Ticktimer");
+            xous::Message::new_blocking_scalar(api::Opcode::ElapsedMs.to_usize().unwrap(),
+                0, 0, 0, 0,
+            )).expect("Ticktimer: failure to send message to Ticktimer");
         if let xous::Result::Scalar2(upper, lower) = response {
             upper as u64 | ((lower as u64) << 32)
         } else {
@@ -33,11 +31,9 @@ impl Ticktimer {
 
     pub fn sleep_ms(&self, ms: usize) -> Result<(), Error> {
         send_message(self.conn,
-            xous::Message::BlockingScalar(xous::ScalarMessage {
-                id: api::Opcode::SleepMs.to_usize().unwrap(),
-                arg1: ms,
-                arg2: 0, arg3: 0, arg4: 0
-            })
+            xous::Message::new_blocking_scalar(api::Opcode::SleepMs.to_usize().unwrap(),
+                 ms,
+                 0, 0, 0)
         ).map(|_| ())
     }
 }
diff --git a/services/trng/src/lib.rs b/services/trng/src/lib.rs
index 5baddfd55..fd70dcfa2 100644
--- a/services/trng/src/lib.rs
+++ b/services/trng/src/lib.rs
@@ -16,10 +16,8 @@ impl Trng {
     }
     pub fn get_u32(&self) -> Result<u32, xous::Error> {
         let response = send_message(self.conn,
-                xous::Message::BlockingScalar(xous::ScalarMessage {
-                    id: api::Opcode::GetTrng.to_usize().unwrap(),
-                    arg1: 1 /* count */, arg2: 0, arg3: 0, arg4: 0
-                })
+            xous::Message::new_blocking_scalar(api::Opcode::GetTrng.to_usize().unwrap(),
+                1 /* count */, 0, 0, 0, )
             ).expect("TRNG|LIB: can't get_u32");
         if let xous::Result::Scalar2(trng, _) = response {
             Ok(trng as u32)
@@ -29,10 +27,8 @@ impl Trng {
     }
     pub fn get_u64(&self) -> Result<u64, xous::Error> {
         let response = send_message(self.conn,
-            xous::Message::BlockingScalar(xous::ScalarMessage {
-                id: api::Opcode::GetTrng.to_usize().unwrap(),
-                arg1: 2 /* count */, arg2: 0, arg3: 0, arg4: 0
-            })
+            xous::Message::new_blocking_scalar(api::Opcode::GetTrng.to_usize().unwrap(),
+                2 /* count */, 0, 0, 0, )
         ).expect("TRNG|LIB: can't get_u32");
     if let xous::Result::Scalar2(lo, hi) = response {
             Ok( lo as u64 | ((hi as u64) << 32) )