added Waveshare BWR Mode for the 4.2in Display (#7995)

Co-authored-by: rrachasak <dev@rachasak.org>
Co-authored-by: clydebarrow <2366188+clydebarrow@users.noreply.github.com>

esphome/components/waveshare_epaper/display.py

@@ -64,6 +64,9 @@ WaveshareEPaper4P2In = waveshare_epaper_ns.class_(
 WaveshareEPaper4P2InBV2 = waveshare_epaper_ns.class_(
     "WaveshareEPaper4P2InBV2", WaveshareEPaper
 )
+WaveshareEPaper4P2InBV2BWR = waveshare_epaper_ns.class_(
+    "WaveshareEPaper4P2InBV2BWR", WaveshareEPaperBWR
+)
 WaveshareEPaper5P8In = waveshare_epaper_ns.class_(
     "WaveshareEPaper5P8In", WaveshareEPaper
 )
@@ -138,6 +141,7 @@ MODELS = {
     "2.90in-dke": ("c", WaveshareEPaper2P9InDKE),
     "4.20in": ("b", WaveshareEPaper4P2In),
     "4.20in-bv2": ("b", WaveshareEPaper4P2InBV2),
+    "4.20in-bv2-bwr": ("b", WaveshareEPaper4P2InBV2BWR),
     "5.83in": ("b", WaveshareEPaper5P8In),
     "5.83inv2": ("b", WaveshareEPaper5P8InV2),
     "7.50in": ("b", WaveshareEPaper7P5In),

esphome/components/waveshare_epaper/waveshare_epaper.cpp

@@ -2274,6 +2274,64 @@ void WaveshareEPaper4P2InBV2::dump_config() {
   LOG_UPDATE_INTERVAL(this);
 }
 
+// ========================================================
+//    4.20in Type B With Red colour support (LUT from OTP)
+// Datasheet:
+//  - https://www.waveshare.com/w/upload/2/20/4.2inch-e-paper-module-user-manual-en.pdf
+//  - https://github.com/waveshare/e-Paper/blob/master/RaspberryPi_JetsonNano/c/lib/e-Paper/EPD_4in2b_V2.c
+// The implementation is an adaptation of WaveshareEPaper4P2InBV2 class
+// ========================================================
+void WaveshareEPaper4P2InBV2BWR::initialize() {
+  // these exact timings are required for a proper reset/init
+  this->reset_pin_->digital_write(false);
+  delay(2);
+  this->reset_pin_->digital_write(true);
+  delay(200);  // NOLINT
+
+  // COMMAND POWER ON
+  this->command(0x04);
+  this->wait_until_idle_();
+
+  // COMMAND PANEL SETTING
+  this->command(0x00);
+  this->data(0x0f);  // LUT from OTP
+}
+
+void HOT WaveshareEPaper4P2InBV2BWR::display() {
+  const uint32_t buf_len = this->get_buffer_length_() / 2u;
+
+  this->command(0x10);  // Send BW data Transmission
+  delay(2);             // Delay to prevent Watchdog error
+  for (uint32_t i = 0; i < buf_len; ++i) {
+    this->data(this->buffer_[i]);
+  }
+
+  this->command(0x13);  // Send red data Transmission
+  delay(2);             // Delay to prevent Watchdog error
+  for (uint32_t i = 0; i < buf_len; ++i) {
+    // Red color need to flip bit from the buffer. Otherwise, red will conqure the screen!
+    this->data(~this->buffer_[buf_len + i]);
+  }
+
+  // COMMAND DISPLAY REFRESH
+  this->command(0x12);
+  this->wait_until_idle_();
+
+  // COMMAND POWER OFF
+  // NOTE: power off < deep sleep
+  this->command(0x02);
+}
+int WaveshareEPaper4P2InBV2BWR::get_width_internal() { return 400; }
+int WaveshareEPaper4P2InBV2BWR::get_height_internal() { return 300; }
+void WaveshareEPaper4P2InBV2BWR::dump_config() {
+  LOG_DISPLAY("", "Waveshare E-Paper", this);
+  ESP_LOGCONFIG(TAG, "  Model: 4.2in (B V2) BWR-Mode");
+  LOG_PIN("  Reset Pin: ", this->reset_pin_);
+  LOG_PIN("  DC Pin: ", this->dc_pin_);
+  LOG_PIN("  Busy Pin: ", this->busy_pin_);
+  LOG_UPDATE_INTERVAL(this);
+}
+
 void WaveshareEPaper5P8In::initialize() {
   // COMMAND POWER SETTING
   this->command(0x01);

esphome/components/waveshare_epaper/waveshare_epaper.h

@@ -518,6 +518,34 @@ class WaveshareEPaper4P2InBV2 : public WaveshareEPaper {
   int get_height_internal() override;
 };
 
+class WaveshareEPaper4P2InBV2BWR : public WaveshareEPaperBWR {
+ public:
+  void initialize() override;
+
+  void display() override;
+
+  void dump_config() override;
+
+  void deep_sleep() override {
+    // COMMAND VCOM AND DATA INTERVAL SETTING
+    this->command(0x50);
+    this->data(0xF7);  // border floating
+
+    // COMMAND POWER OFF
+    this->command(0x02);
+    this->wait_until_idle_();
+
+    // COMMAND DEEP SLEEP
+    this->command(0x07);
+    this->data(0xA5);  // check code
+  }
+
+ protected:
+  int get_width_internal() override;
+
+  int get_height_internal() override;
+};
+
 class WaveshareEPaper5P8In : public WaveshareEPaper {
  public:
   void initialize() override;

tests/components/waveshare_epaper/common.yaml

@@ -502,6 +502,25 @@ display:
     lambda: |-
       it.rectangle(0, 0, it.get_width(), it.get_height());
 
+  - platform: waveshare_epaper
+    id: epd_4_20in_bv2_bwr
+    model: 4.20in-bv2-bwr
+    spi_id: spi_waveshare_epaper
+    cs_pin:
+      allow_other_uses: true
+      number: ${cs_pin}
+    dc_pin:
+      allow_other_uses: true
+      number: ${dc_pin}
+    busy_pin:
+      allow_other_uses: true
+      number: ${busy_pin}
+    reset_pin:
+      allow_other_uses: true
+      number: ${reset_pin}
+    lambda: |-
+      it.rectangle(0, 0, it.get_width(), it.get_height());
+
   # 5.83 inch displays
   - platform: waveshare_epaper
     id: epd_5_83