From 82a1aa37dbfb060406ed72f28e511786010c8f5f Mon Sep 17 00:00:00 2001
From: Eric Katzfey <53063038+katzfey@users.noreply.github.com>
Date: Thu, 21 Mar 2024 17:54:43 -0700
Subject: [PATCH] uORB: fix for uORB communicator, only send most recent data
 for new subscription (#22893)

---
 platforms/common/uORB/uORBDeviceNode.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/platforms/common/uORB/uORBDeviceNode.cpp b/platforms/common/uORB/uORBDeviceNode.cpp
index e83b3f3e04..fd4ef60e63 100644
--- a/platforms/common/uORB/uORBDeviceNode.cpp
+++ b/platforms/common/uORB/uORBDeviceNode.cpp
@@ -412,7 +412,10 @@ int16_t uORB::DeviceNode::process_add_subscription()
 	uORBCommunicator::IChannel *ch = uORB::Manager::get_instance()->get_uorb_communicator();
 
 	if (_data != nullptr && ch != nullptr) { // _data will not be null if there is a publisher.
-		ch->send_message(_meta->o_name, _meta->o_size, _data);
+		// Only send the most recent data to initialize the remote end.
+		if (_data_valid) {
+			ch->send_message(_meta->o_name, _meta->o_size, _data + (_meta->o_size * ((_generation.load() - 1) % _meta->o_queue)));
+		}
 	}
 
 	return PX4_OK;