stm32: can: fd: fix SID read/write from buf elems

1 files changed, 4 insertions, 2 deletions

diff --git a/embassy-stm32/src/can/fd/peripheral.rs b/embassy-stm32/src/can/fd/peripheral.rs
index 0771d6fbb..8e4ecf4a5 100644
--- a/embassy-stm32/src/can/fd/peripheral.rs
+++ b/embassy-stm32/src/can/fd/peripheral.rs
@@ -721,13 +721,15 @@ fn make_id(id: u32, extended: bool) -> embedded_can::Id {
     if extended {
         embedded_can::Id::from(unsafe { embedded_can::ExtendedId::new_unchecked(id & 0x1FFFFFFF) })
     } else {
-        embedded_can::Id::from(unsafe { embedded_can::StandardId::new_unchecked((id & 0x000007FF) as u16) })
+        // A standard identifier is stored into ID[28:18].
+        embedded_can::Id::from(unsafe { embedded_can::StandardId::new_unchecked(((id >> 18) & 0x000007FF) as u16) })
     }
 }
 
 fn put_tx_header(mailbox: &mut TxBufferElement, header: &Header) {
     let (id, id_type) = match header.id() {
-        embedded_can::Id::Standard(id) => (id.as_raw() as u32, IdType::StandardId),
+        // A standard identifier has to be written to ID[28:18].
+        embedded_can::Id::Standard(id) => ((id.as_raw() as u32) << 18, IdType::StandardId),
         embedded_can::Id::Extended(id) => (id.as_raw() as u32, IdType::ExtendedId),
     };