From aad03f1bf59e4e812109a6311422411cf748affd Mon Sep 17 00:00:00 2001
From: Tercio Filho <terciofilho@gmail.com>
Date: Mon, 13 Sep 2021 10:36:01 -0300
Subject: [PATCH] Fix issue #2054. PZEM004T Component doesn't set the module
 address. (#1784)

---
 esphome/components/pzem004t/pzem004t.cpp | 8 ++++++++
 esphome/components/pzem004t/pzem004t.h   | 2 ++
 2 files changed, 10 insertions(+)

diff --git a/esphome/components/pzem004t/pzem004t.cpp b/esphome/components/pzem004t/pzem004t.cpp
index 969ce8fa10..e5418765bd 100644
--- a/esphome/components/pzem004t/pzem004t.cpp
+++ b/esphome/components/pzem004t/pzem004t.cpp
@@ -6,6 +6,14 @@ namespace pzem004t {
 
 static const char *const TAG = "pzem004t";
 
+void PZEM004T::setup() {
+  // Clear UART buffer
+  while (this->available())
+    this->read();
+  // Set module address
+  this->write_state_(SET_ADDRESS);
+}
+
 void PZEM004T::loop() {
   const uint32_t now = millis();
   if (now - this->last_read_ > 500 && this->available() < 7) {
diff --git a/esphome/components/pzem004t/pzem004t.h b/esphome/components/pzem004t/pzem004t.h
index 517b81eb21..f4f9f29b4d 100644
--- a/esphome/components/pzem004t/pzem004t.h
+++ b/esphome/components/pzem004t/pzem004t.h
@@ -14,6 +14,8 @@ class PZEM004T : public PollingComponent, public uart::UARTDevice {
   void set_power_sensor(sensor::Sensor *power_sensor) { power_sensor_ = power_sensor; }
   void set_energy_sensor(sensor::Sensor *energy_sensor) { energy_sensor_ = energy_sensor; }
 
+  void setup() override;
+
   void loop() override;
 
   void update() override;