From 910570cd0b7b5128686d02d121828406a356f1b4 Mon Sep 17 00:00:00 2001
From: ElVit <vitalij.salnikov@t-online.de>
Date: Mon, 23 Mar 2026 19:40:17 +0100
Subject: [PATCH 1/2] Revert "Do not chunk uart messages"

This reverts commit 49067807071477d66f5e8cde66a52e24cdf1e974.
---
 components/panasonic_heatpump/helpers.cpp | 6 +++++-
 components/panasonic_heatpump/helpers.h   | 4 ++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/components/panasonic_heatpump/helpers.cpp b/components/panasonic_heatpump/helpers.cpp
index 29e5b71..a2fdaf8 100644
--- a/components/panasonic_heatpump/helpers.cpp
+++ b/components/panasonic_heatpump/helpers.cpp
@@ -32,7 +32,11 @@ void PanasonicHelpers::log_uart_hex(UartLogDirection direction, const uint8_t* d
   delay(10);
 
   logStr += byte_array_to_hex_string(data, length, separator);
-  ESP_LOGI(TAG, "%s %s", msgDir.c_str(), logStr.c_str());
+
+  for (size_t i = 0; i < logStr.length(); i += UART_LOG_CHUNK_SIZE) {
+    ESP_LOGI(TAG, "%s %s", msgDir.c_str(), logStr.substr(i, UART_LOG_CHUNK_SIZE).c_str());
+    delay(10);
+  }
 }
 
 std::string PanasonicHelpers::byte_array_to_hex_string(const std::vector<uint8_t>& data, const char separator) {
diff --git a/components/panasonic_heatpump/helpers.h b/components/panasonic_heatpump/helpers.h
index 042234a..af71f9c 100644
--- a/components/panasonic_heatpump/helpers.h
+++ b/components/panasonic_heatpump/helpers.h
@@ -5,6 +5,10 @@
 #include <vector>
 #include <string>
 
+#ifndef UART_LOG_CHUNK_SIZE
+#define UART_LOG_CHUNK_SIZE 120
+#endif
+
 namespace esphome {
 namespace panasonic_heatpump {
 enum UartLogDirection : uint8_t {

From 1410f1676edc495a778b72df6ac3aa5638be47f9 Mon Sep 17 00:00:00 2001
From: ElVit <vitalij.salnikov@t-online.de>
Date: Mon, 23 Mar 2026 19:49:00 +0100
Subject: [PATCH 2/2] Add comment to explain why chunking log messages

---
 components/panasonic_heatpump/helpers.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/components/panasonic_heatpump/helpers.cpp b/components/panasonic_heatpump/helpers.cpp
index a2fdaf8..5546ea0 100644
--- a/components/panasonic_heatpump/helpers.cpp
+++ b/components/panasonic_heatpump/helpers.cpp
@@ -33,6 +33,8 @@ void PanasonicHelpers::log_uart_hex(UartLogDirection direction, const uint8_t* d
 
   logStr += byte_array_to_hex_string(data, length, separator);
 
+  // Log in chunks to avoid ESP_LOG buffer overflow (https://developers.esphome.io/architecture/logging/).
+  // The default log buffer is 512 bytes but UART messages can be larger (203 * 3 = 609 characters + log header).
   for (size_t i = 0; i < logStr.length(); i += UART_LOG_CHUNK_SIZE) {
     ESP_LOGI(TAG, "%s %s", msgDir.c_str(), logStr.substr(i, UART_LOG_CHUNK_SIZE).c_str());
     delay(10);