add support for multiple Pylontech batteries

This release supports more than one Pylontech batteries via RS485.
Set all battery ADD switches to X000 (default Address and 115200 Baud)
Alle batteries linked via the Link Ports
First battery is the Master battery and has do be connected via RS485 to
the OpenDTU-onBattery (my special edition)
the other batteries are Slave-1 to Slave-n
Currently this version only supports 2 batteries (Master + Slave-1)
Set the "Number of batteries" in the Battery Admin GUI to the amount of
batteries you have,
The GUI exepts values between 1 and 5 for future releases but actually
it will be limited to 2 in the WebApi_battery.cpp backend.

include/BatteryStats.h

@@ -8,6 +8,7 @@
 #include "JkBmsDataPoints.h"
 #include "VeDirectShuntController.h"
 #include "Configuration.h"
+#include "defaults.h"
 
 #pragma pack(push, 1)
 typedef union {
@@ -417,7 +418,7 @@ class PylontechRS485BatteryStats : public BatteryStats {
         ModuleSerialNumber_t ModuleSerialNumber;
     };
 
-    Pack_t Pack[2];
+    Pack_t Pack[MAX_BATTERIES];
 /*
     String softwareVersion;
     String _manufacturerVersion;

include/defaults.h

@@ -156,6 +156,7 @@
 #define POWERLIMITER_FULL_SOLAR_PASSTHROUGH_START_VOLTAGE 100
 #define POWERLIMITER_FULL_SOLAR_PASSTHROUGH_STOP_VOLTAGE 100
 
+#define MAX_BATTERIES   2   // currently only 2 Pylontech Batteries are supported (Master and one Slave)
 #define BATTERY_ENABLED false
 #define BATTERY_PROVIDER 0 // Pylontech RS485 receiver
 #define BATTERY_JKBMS_INTERFACE 0

src/PylontechRS485Receiver.cpp

@@ -12,6 +12,7 @@
 #include "PinMapping.h"
 #include <Arduino.h>
 #include <ctime>
+#include "defaults.h"
 
 static constexpr char TAG[] = "[Pylontech RS485]";
 
@@ -70,10 +71,11 @@ bool PylontechRS485Receiver::init()
     Battery._verboseLogging = true;
 
     _masterBatteryID = 2;   // Master battery starts with ID = 2
-    _lastSlaveBatteryID = _masterBatteryID + Configuration.get().Battery.numberOfBatteries;
 
     get_pack_count(REQUEST_AND_GET, _masterBatteryID);
 
+    _lastSlaveBatteryID = _masterBatteryID + _stats->_number_of_packs;
+
     for (uint8_t i=_masterBatteryID; i<_lastSlaveBatteryID; i++) {
         MessageOutput.printf("%s %s Battery Pack %d\r\n", TAG, i==2 ? "Master" : "Slave", i);
         get_protocol_version(REQUEST_AND_GET, i);
@@ -319,6 +321,8 @@ void PylontechRS485Receiver::get_pack_count(const PylontechRS485Receiver::Functi
     }
 
     _stats->_number_of_packs = f->info[0];
+    if (_stats->_number_of_packs > MAX_BATTERIES) _stats->_number_of_packs = MAX_BATTERIES; // currently limited to max 2 batteries (see default.h)
+    if (_stats->_number_of_packs > Configuration.get().Battery.numberOfBatteries) _stats->_number_of_packs = Configuration.get().Battery.numberOfBatteries;
 
     if (Battery._verboseLogging) MessageOutput.printf("%s::%s Number of Battery Packs %u\r\n", TAG, __FUNCTION__, _stats->_number_of_packs);
 }

src/WebApi_battery.cpp

@@ -12,6 +12,7 @@
 #include "WebApi_battery.h"
 #include "WebApi_errors.h"
 #include "helper.h"
+#include "defaults.h"
 
 void WebApiBatteryClass::init(AsyncWebServer& server, Scheduler& scheduler)
 {
@@ -147,6 +148,9 @@ void WebApiBatteryClass::onAdminPost(AsyncWebServerRequest* request)
     cBattery.MaxChargeTemperature = root["max_charge_temp"].as<int8_t>();
     cBattery.MinDischargeTemperature = root["min_discharge_temp"].as<int8_t>();
     cBattery.MaxDischargeTemperature = root["max_discharge_temp"].as<int8_t>();
+    cBattery.numberOfBatteries = root["numberOfBatteries"].as<int8_t>();
+    if (Configuration.get().Battery.numberOfBatteries > MAX_BATTERIES) Configuration.get().Battery.numberOfBatteries = MAX_BATTERIES;
+
 #ifdef USE_MQTT_BATTERY
     strlcpy(cBattery.Mqtt.SocTopic, root["mqtt_soc_topic"].as<String>().c_str(), sizeof(cBattery.Mqtt.SocTopic));
     strlcpy(cBattery.Mqtt.VoltageTopic, root["mqtt_voltage_topic"].as<String>().c_str(), sizeof(cBattery.Mqtt.VoltageTopic));

src/WebApi_ws_battery.cpp

@@ -57,7 +57,7 @@ void WebApiWsBatteryLiveClass::sendDataTaskCb()
     _lastUpdateCheck = millis();
 
     for (uint8_t i=0; i< Battery.getStats()->get_number_of_packs(); i++) {
-//    for (uint8_t i=0; i<2; i++) {
+//    for (uint8_t i=0; i<MAX_BATTERIES; i++) {
 
     try {
         std::lock_guard<std::mutex> lock(_mutex);
@@ -114,14 +114,14 @@ void WebApiWsBatteryLiveClass::onLivedataStatus(AsyncWebServerRequest* request)
 
     try {
         std::lock_guard<std::mutex> lock(_mutex);
-        AsyncJsonResponse* response = new AsyncJsonResponse(false, _responseSize*3);
+        AsyncJsonResponse* response = new AsyncJsonResponse(false, _responseSize + MAX_BATTERIES*_responseSize);
         auto& root = response->getRoot();
 
         generateJsonResponse(root);
 
         JsonArray packsArray = root.createNestedArray("packs");
         for (uint8_t i=0; i< Battery.getStats()->get_number_of_packs(); i++) {
-//        for (uint8_t i=0; i<2; i++) {
+//        for (uint8_t i=0; i<MAX_BATTERIES; i++) {
             JsonObject packObject = packsArray.createNestedObject();
             Battery.getStats()->generatePackCommonJsonResponse(packObject, i);
         }