From 9a820356ff0e2f45e3fe9e17fe1f4c59891f391e Mon Sep 17 00:00:00 2001
From: Jannik Beyerstedt <beyerstedt@consider-it.de>
Date: Tue, 29 Sep 2026 15:25:16 +0200
Subject: [PATCH] ble: Set short name in advertisement

---
 src/ble.rs  | 13 +++++++++----
 src/main.rs |  5 +++--
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/src/ble.rs b/src/ble.rs
index a460d4e..ba2ce99 100644
--- a/src/ble.rs
+++ b/src/ble.rs
@@ -110,6 +110,7 @@ pub async fn run(
         CONTROLLER_SLOTS,
     >,
     name: alloc::string::String,
+    short_name: alloc::string::String,
 ) {
     let mut resources: HostResources<DefaultPacketPool, CONNECTIONS_MAX, L2CAP_CHANNELS_MAX> =
         HostResources::new();
@@ -120,6 +121,7 @@ pub async fn run(
         ..
     } = stack.build();
 
+    info!("BLE name: {name} (short: {short_name})");
     info!(
         "Starting advertising and GATT service for {}",
         crate::util::get_rx_feature_list().join(",")
@@ -132,7 +134,7 @@ pub async fn run(
 
     let _ = embassy_futures::join::join(ble_task(runner), async {
         loop {
-            match advertise(&mut peripheral, &server).await {
+            match advertise(&mut peripheral, &server, &short_name).await {
                 Ok(conn) => {
                     info!("BLE: New client connected");
 
@@ -176,16 +178,19 @@ pub fn update(payload: BleSendable) {
 async fn advertise<'values, 'server, C: Controller>(
     peripheral: &mut Peripheral<'values, C, DefaultPacketPool>,
     server: &'server Server<'values>,
+    // name in advertisement, max. 8 characters
+    short_name: &'values str,
 ) -> Result<GattConnection<'values, 'server, DefaultPacketPool>, BleHostError<C::Error>> {
-    let mut advertiser_data = [0; 35];
+    let mut advertiser_data = [0; 31]; // 37 bytes payload - 6 byte address
     let service_uuid = Uuid::from(0xc0b7_0000_d4f4_4000_ada8_f99a_02ee_315c_u128)
         .as_raw()
         .try_into()
         .unwrap();
     let len = AdStructure::encode_slice(
         &[
-            AdStructure::Flags(LE_GENERAL_DISCOVERABLE | BR_EDR_NOT_SUPPORTED),
-            AdStructure::ServiceUuids128(&[service_uuid]),
+            AdStructure::Flags(LE_GENERAL_DISCOVERABLE | BR_EDR_NOT_SUPPORTED), // 2+ 1 byte
+            AdStructure::ServiceUuids128(&[service_uuid]),                      // 2+16 byte = 21
+            AdStructure::ShortenedLocalName(short_name.as_bytes()),             // 2+ 8 byte = 31
         ],
         &mut advertiser_data[..],
     )?;
diff --git a/src/main.rs b/src/main.rs
index 5c23fe6..57a8963 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -222,12 +222,13 @@ async fn main(spawner: Spawner) -> ! {
         let controller = ble::make_controller(peripherals.BT);
         let serial = &mac.as_bytes()[3..6];
         let name = alloc::format!(
-            "ESP32 C-ITS {:02x}{:02x}{:02x}",
+            "C-ITS ESP {:02x}:{:02x}:{:02x}",
             serial[0],
             serial[1],
             serial[2]
         );
-        spawner.spawn(ble::run(controller, name).expect("Failed to spawn BLE task"));
+        let short_name = alloc::format!("V2X {:02x}{:02x}", serial[1], serial[2]); // max 8 chars!
+        spawner.spawn(ble::run(controller, name, short_name).expect("Failed to spawn BLE task"));
     }
 
     // Setup GNSS: