Fix preamble synchronization (#42)

components/votronic/votronic.cpp

@@ -23,6 +23,7 @@ static const uint8_t VOTRONIC_FRAME_TYPE_BATTERY_COMPUTER_INFO3 = 0xFA;
 
 static const uint8_t VOTRONIC_FRAME_TYPE_CONTROL_CHARGER = 0x7A;             // Incorrect protocol description?
 static const uint8_t VOTRONIC_FRAME_TYPE_CONTROL_CHARGING_CONVERTER = 0x3A;  // Incorrect protocol description?
+static const uint8_t VOTRONIC_FRAME_TYPE_CONTROL_CHARGING_CONVERTER2 = 0x4A;
 static const uint8_t VOTRONIC_FRAME_TYPE_CONTROL_BATTERY_COMPUTER = 0xEA;
 
 static const uint8_t BATTERY_STATUS_SIZE = 8;
@@ -65,6 +66,8 @@ void Votronic::loop() {
   const uint32_t now = millis();
 
   if (now - this->last_byte_ > this->rx_timeout_) {
+    ESP_LOGVV(TAG, "Buffer cleared due to timeout: %s",
+              format_hex_pretty(&this->rx_buffer_.front(), this->rx_buffer_.size()).c_str());
     this->rx_buffer_.clear();
     this->last_byte_ = now;
   }
@@ -75,6 +78,8 @@ void Votronic::loop() {
     if (this->parse_votronic_byte_(byte)) {
       this->last_byte_ = now;
     } else {
+      ESP_LOGVV(TAG, "Buffer cleared due to reset: %s",
+                format_hex_pretty(&this->rx_buffer_.front(), this->rx_buffer_.size()).c_str());
       this->rx_buffer_.clear();
     }
   }
@@ -88,11 +93,8 @@ bool Votronic::parse_votronic_byte_(uint8_t byte) {
   const uint8_t *raw = &this->rx_buffer_[0];
   const uint8_t frame_len = VOTRONIC_FRAME_LENGTH;
 
-  if (at == 0)
-    return true;
-
-  if (raw[0] != VOTRONIC_FRAME_START) {
-    ESP_LOGW(TAG, "Invalid header");
+  if (at == 0 && raw[0] != VOTRONIC_FRAME_START) {
+    ESP_LOGW(TAG, "Invalid header (0x%02X)", raw[0]);
 
     // return false to reset buffer
     return false;
@@ -143,6 +145,12 @@ void Votronic::on_votronic_data(const std::vector<uint8_t> &data) {
     case VOTRONIC_FRAME_TYPE_BATTERY_COMPUTER_INFO3:
       this->decode_battery_computer_info3_data_(data);
       break;
+    case VOTRONIC_FRAME_TYPE_CONTROL_CHARGING_CONVERTER2:
+      // Skip empty frame silently
+      // 0xAA 0x4A 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x4A
+      if (data[VOTRONIC_FRAME_LENGTH - 1] == VOTRONIC_FRAME_TYPE_CONTROL_CHARGING_CONVERTER2) {
+        break;
+      }
     default:
       ESP_LOGW(TAG, "Your device is probably not supported. Please create an issue here: "
                     "https://github.com/syssi/esphome-votronic/issues");

tests/esp8266-fake-charger-vbcs-triple.yaml

@@ -0,0 +1,59 @@
+# Battery Charger VBCS 60/40/430 Triple-CI (3246)
+# See https://github.com/syssi/esphome-votronic/issues/41
+
+substitutions:
+  name: fake-charger
+  device_description: "Emulate the Display-Link port traffic of a Votronic Charger"
+  tx_pin: GPIO4
+  rx_pin: GPIO5
+
+esphome:
+  name: ${name}
+  comment: ${device_description}
+  project:
+    name: "syssi.esphome-votronic"
+    version: 2.0.0
+
+esp8266:
+  board: d1_mini
+
+wifi:
+  ssid: !secret wifi_ssid
+  password: !secret wifi_password
+
+ota:
+
+logger:
+  level: DEBUG
+
+api:
+  reboot_timeout: 0s
+
+uart:
+  baud_rate: 1000
+  tx_pin: ${tx_pin}
+  rx_pin: ${rx_pin}
+  debug:
+    direction: BOTH
+    dummy_receiver: true
+
+interval:
+  - interval: 10s
+    then:
+      - uart.write: [0xAA, 0x3A, 0x67, 0x05, 0xDD, 0x04, 0x00, 0x00, 0x00, 0x01, 0x00, 0xA6, 0x56, 0x28, 0x00, 0x58]
+      - uart.write: [0xAA, 0x7A, 0x68, 0x05, 0xDD, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0xA6, 0x56, 0x28, 0x00, 0x16]
+      - uart.write: [0xAA, 0x1A, 0x68, 0x05, 0x74, 0x08, 0x00, 0x00, 0x00, 0xE0, 0xA6, 0x1F, 0x56, 0x22, 0x19, 0x3F]
+      - uart.write: [0xAA, 0x4A, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x4A]
+      - delay: 2s
+
+      - uart.write: [0xAA, 0x7A, 0x68, 0x05, 0xDE, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0xA6, 0x56, 0x28, 0x00, 0x15]
+      - uart.write: [0xAA, 0x1A, 0x67, 0x05, 0x72, 0x08, 0x00, 0x00, 0x00, 0xE0, 0xA6, 0x1F, 0x56, 0x22, 0x19, 0x36]
+      - uart.write: [0xAA, 0x3A, 0x68, 0x05, 0xDE, 0x04, 0x00, 0x00, 0x00, 0x01, 0x00, 0xA6, 0x56, 0x28, 0x00, 0x54]
+      - uart.write: [0xAA, 0x4A, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x4A]
+      - delay: 2s
+
+      - uart.write: [0xAA, 0x7A, 0x67, 0x05, 0xDD, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0xA6, 0x56, 0x28, 0x00, 0x19]
+      - uart.write: [0xAA, 0x1A, 0x68, 0x05, 0x72, 0x08, 0x00, 0x00, 0x00, 0xE0, 0xA6, 0x1F, 0x56, 0x22, 0x19, 0x39]
+      - uart.write: [0xAA, 0x3A, 0x67, 0x05, 0xDD, 0x04, 0x00, 0x00, 0x00, 0x01, 0x00, 0xA6, 0x56, 0x28, 0x00, 0x58]
+      - uart.write: [0xAA, 0x4A, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x4A]
+      - delay: 2s