feat(battery): round bat_v and derive bat_pct locally

include/power_manager.h

@@ -6,4 +6,5 @@
 void power_sender_init();
 void power_receiver_init();
 void read_battery(MeterData &data);
+uint8_t battery_percent_from_voltage(float voltage_v);
 void go_to_deep_sleep(uint32_t seconds);

include/test_mode.h

@@ -5,5 +5,5 @@
 
 #ifdef ENABLE_TEST_MODE
 void test_sender_loop(uint16_t short_id, const char *device_id);
-void test_receiver_loop(SenderStatus *statuses, uint8_t count);
+void test_receiver_loop(SenderStatus *statuses, uint8_t count, uint16_t self_short_id);
 #endif

src/json_codec.cpp

@@ -1,9 +1,10 @@
 #include "json_codec.h"
 #include <ArduinoJson.h>
 #include <math.h>
+#include "power_manager.h"
 
 bool meterDataToJson(const MeterData &data, String &out_json) {
-  StaticJsonDocument<256> doc;
+  StaticJsonDocument<192> doc;
   doc["id"] = data.device_id;
   doc["ts"] = data.ts_utc;
   doc["energy_kwh"] = data.energy_total_kwh;
@@ -14,8 +15,9 @@ bool meterDataToJson(const MeterData &data, String &out_json) {
   doc["v1_v"] = data.phase_voltage_v[0];
   doc["v2_v"] = data.phase_voltage_v[1];
   doc["v3_v"] = data.phase_voltage_v[2];
-  doc["bat_v"] = data.battery_voltage_v;
+  char bat_buf[8];
-  doc["bat_pct"] = data.battery_percent;
+  snprintf(bat_buf, sizeof(bat_buf), "%.2f", data.battery_voltage_v);
+  doc["bat_v"] = serialized(bat_buf);
 
   out_json = "";
   size_t len = serializeJson(doc, out_json);
@@ -23,7 +25,7 @@ bool meterDataToJson(const MeterData &data, String &out_json) {
 }
 
 bool jsonToMeterData(const String &json, MeterData &data) {
-  StaticJsonDocument<256> doc;
+  StaticJsonDocument<192> doc;
   DeserializationError err = deserializeJson(doc, json);
   if (err) {
     return false;
@@ -43,7 +45,11 @@ bool jsonToMeterData(const String &json, MeterData &data) {
   data.phase_voltage_v[1] = doc["v2_v"] | NAN;
   data.phase_voltage_v[2] = doc["v3_v"] | NAN;
   data.battery_voltage_v = doc["bat_v"] | NAN;
-  data.battery_percent = doc["bat_pct"] | 0;
+  if (doc["bat_pct"].isNull() && !isnan(data.battery_voltage_v)) {
+    data.battery_percent = battery_percent_from_voltage(data.battery_voltage_v);
+  } else {
+    data.battery_percent = doc["bat_pct"] | 0;
+  }
   data.valid = true;
 
   if (strlen(data.device_id) >= 8) {

src/main.cpp

@@ -164,7 +164,7 @@ void loop() {
     display_tick();
     delay(50);
   } else {
-    test_receiver_loop(g_sender_statuses, NUM_SENDERS);
+    test_receiver_loop(g_sender_statuses, NUM_SENDERS, g_short_id);
     mqtt_loop();
     web_server_loop();
     display_set_receiver_status(g_ap_mode, wifi_is_connected() ? wifi_get_ssid().c_str() : "AP", mqtt_is_connected());

src/power_manager.cpp

@@ -32,14 +32,18 @@ void read_battery(MeterData &data) {
   float v = (avg / 4095.0f) * ADC_REF_V * BATTERY_DIVIDER * BATTERY_CAL;
 
   data.battery_voltage_v = v;
-  float pct = (v - 3.0f) / (4.2f - 3.0f) * 100.0f;
+  data.battery_percent = battery_percent_from_voltage(v);
+}
+
+uint8_t battery_percent_from_voltage(float voltage_v) {
+  float pct = (voltage_v - 3.0f) / (4.2f - 3.0f) * 100.0f;
   if (pct < 0.0f) {
     pct = 0.0f;
   }
   if (pct > 100.0f) {
     pct = 100.0f;
   }
-  data.battery_percent = static_cast<uint8_t>(pct + 0.5f);
+  return static_cast<uint8_t>(pct + 0.5f);
 }
 
 void go_to_deep_sleep(uint32_t seconds) {

src/test_mode.cpp

@@ -8,10 +8,14 @@
 #include "time_manager.h"
 #include "display_ui.h"
 #include "mqtt_client.h"
+#include "power_manager.h"
 #include <ArduinoJson.h>
+#include <math.h>
 
 static uint32_t g_last_test_ms = 0;
+static uint16_t g_test_code_counter = 1000;
 static uint32_t g_last_timesync_ms = 0;
+static constexpr uint32_t TEST_SEND_INTERVAL_MS = 30000;
 
 void test_sender_loop(uint16_t short_id, const char *device_id) {
   LoraPacket rx = {};
@@ -19,25 +23,42 @@ void test_sender_loop(uint16_t short_id, const char *device_id) {
     time_handle_timesync_payload(rx.payload, rx.payload_len);
   }
 
-  if (millis() - g_last_test_ms < 30000) {
+  if (millis() - g_last_test_ms < TEST_SEND_INTERVAL_MS) {
     return;
   }
   g_last_test_ms = millis();
 
   char code[5];
-  uint16_t val = random(0, 9999);
+  snprintf(code, sizeof(code), "%04u", g_test_code_counter);
-  snprintf(code, sizeof(code), "%04u", val);
+  g_test_code_counter++;
+  if (g_test_code_counter > 9999) {
+    g_test_code_counter = 1000;
+  }
   display_set_test_code(code);
 
+  MeterData data = {};
+  data.short_id = short_id;
+  strncpy(data.device_id, device_id, sizeof(data.device_id));
+  read_battery(data);
+
+  uint32_t now_utc = time_get_utc();
+  uint32_t ts = now_utc > 0 ? now_utc : millis() / 1000;
+
   StaticJsonDocument<128> doc;
   doc["id"] = device_id;
   doc["role"] = "sender";
   doc["test_code"] = code;
-  doc["ts"] = time_get_utc();
+  doc["ts"] = ts;
+  char bat_buf[8];
+  snprintf(bat_buf, sizeof(bat_buf), "%.2f", data.battery_voltage_v);
+  doc["bat_v"] = serialized(bat_buf);
 
   String json;
   serializeJson(doc, json);
 
+  data.ts_utc = ts;
+  display_set_last_meter(data);
+
   uint8_t compressed[LORA_MAX_PAYLOAD];
   size_t compressed_len = 0;
   if (!compressBuffer(reinterpret_cast<const uint8_t *>(json.c_str()), json.length(), compressed, sizeof(compressed), compressed_len)) {
@@ -54,10 +75,10 @@ void test_sender_loop(uint16_t short_id, const char *device_id) {
   lora_send(pkt);
 }
 
-void test_receiver_loop(SenderStatus *statuses, uint8_t count) {
+void test_receiver_loop(SenderStatus *statuses, uint8_t count, uint16_t self_short_id) {
   if (millis() - g_last_timesync_ms > TIME_SYNC_INTERVAL_SEC * 1000UL) {
     g_last_timesync_ms = millis();
-    time_send_timesync(0);
+    time_send_timesync(self_short_id);
   }
 
   LoraPacket pkt = {};
@@ -68,7 +89,7 @@ void test_receiver_loop(SenderStatus *statuses, uint8_t count) {
     return;
   }
 
-  uint8_t decompressed[128];
+  uint8_t decompressed[160];
   size_t decompressed_len = 0;
   if (!decompressBuffer(pkt.payload, pkt.payload_len, decompressed, sizeof(decompressed), decompressed_len)) {
     return;
@@ -82,10 +103,15 @@ void test_receiver_loop(SenderStatus *statuses, uint8_t count) {
 
   const char *id = doc["id"] | "";
   const char *code = doc["test_code"] | "";
+  float bat_v = doc["bat_v"] | NAN;
 
   for (uint8_t i = 0; i < count; ++i) {
     if (strncmp(statuses[i].last_data.device_id, id, sizeof(statuses[i].last_data.device_id)) == 0) {
       display_set_test_code_for_sender(i, code);
+      if (!isnan(bat_v)) {
+        statuses[i].last_data.battery_voltage_v = bat_v;
+        statuses[i].last_data.battery_percent = battery_percent_from_voltage(bat_v);
+      }
       statuses[i].has_data = true;
       statuses[i].last_update_ts_utc = time_get_utc();
       break;