Fix relation between RSSI and signal strength

Fix relation between RSSI and signal strength

RELEASENOTES.md

@@ -75,6 +75,7 @@ The following binary downloads have been compiled with ESP8266/Arduino library c
 - Fix PWM flickering at low levels (#7415)
 - Fix Hass sensor discovery part 1/4 by Federico Leoni (#7582, #7548)
 - Fix MaxPower functionality (#7647)
+- Fix relation between RSSI and signal strength
 - Add command ``SetOption79 0/1`` to enable reset of counters at teleperiod time by Andre Thomas (#7355)
 - Add command ``SetOption82 0/1`` to limit the CT range for Alexa to 200..380
 - Add command ``SetOption84 1`` to send AWS IoT device shadow updates (alternative to retained)

tasmota/CHANGELOG.md

@@ -5,6 +5,7 @@
 - Change MQTT message size with additional 200 characters
 - Change some wifi code to attempt faster connection (#7621)
 - Change display of some date and time messages from "Wed Feb 19 10:45:12 2020" to "2020-02-19T10:45:12"
+- Fix relation between RSSI and signal strength
 - Add another new DHT driver based on ESPEasy. The old driver can still be used using define USE_DHT_OLD. The previous new driver can be used with define USE_DHT_V2 (#7717)
 
 ### 8.1.0.7 20200210

tasmota/support.ino

@@ -51,7 +51,8 @@ void OsWatchTicker(void)
   uint32_t last_run = abs(t - oswatch_last_loop_time);
 
 #ifdef DEBUG_THEO
-  AddLog_P2(LOG_LEVEL_DEBUG, PSTR(D_LOG_APPLICATION D_OSWATCH " FreeRam %d, rssi %d %% (%d dBm), last_run %d"), ESP.getFreeHeap(), WifiGetRssiAsQuality(WiFi.RSSI()), WiFi.RSSI(), last_run);
+  int32_t rssi = WiFi.RSSI();
+  AddLog_P2(LOG_LEVEL_DEBUG, PSTR(D_LOG_APPLICATION D_OSWATCH " FreeRam %d, rssi %d %% (%d dBm), last_run %d"), ESP.getFreeHeap(), WifiGetRssiAsQuality(rssi), rssi, last_run);
 #endif  // DEBUG_THEO
   if (last_run >= (OSWATCH_RESET_TIME * 1000)) {
 //    AddLog_P(LOG_LEVEL_INFO, PSTR(D_LOG_APPLICATION D_OSWATCH " " D_BLOCKED_LOOP ". " D_RESTARTING));  // Save iram space

tasmota/support_tasmota.ino

@@ -647,9 +647,10 @@ void MqttShowState(void)
     MqttShowPWMState();
   }
 
+  int32_t rssi = WiFi.RSSI();
   ResponseAppend_P(PSTR(",\"" D_JSON_WIFI "\":{\"" D_JSON_AP "\":%d,\"" D_JSON_SSID "\":\"%s\",\"" D_JSON_BSSID "\":\"%s\",\"" D_JSON_CHANNEL "\":%d,\"" D_JSON_RSSI "\":%d,\"" D_JSON_SIGNAL "\":%d,\"" D_JSON_LINK_COUNT "\":%d,\"" D_JSON_DOWNTIME "\":\"%s\"}}"),
     Settings.sta_active +1, SettingsText(SET_STASSID1 + Settings.sta_active), WiFi.BSSIDstr().c_str(), WiFi.channel(),
-    WifiGetRssiAsQuality(WiFi.RSSI()), WiFi.RSSI(), WifiLinkCount(), WifiDowntime().c_str());
+    WifiGetRssiAsQuality(rssi), rssi, WifiLinkCount(), WifiDowntime().c_str());
 }
 
 void MqttPublishTeleState(void)

tasmota/xdrv_01_webserver.ino

@@ -1719,16 +1719,17 @@ void HandleWifiConfiguration(void)
         //display networks in page
         for (uint32_t i = 0; i < n; i++) {
           if (-1 == indices[i]) { continue; }  // skip dups
+          int32_t rssi = WiFi.RSSI(indices[i])
           DEBUG_CORE_LOG(PSTR(D_LOG_WIFI D_SSID " %s, " D_BSSID " %s, " D_CHANNEL " %d, " D_RSSI " %d"),
-            WiFi.SSID(indices[i]).c_str(), WiFi.BSSIDstr(indices[i]).c_str(), WiFi.channel(indices[i]), WiFi.RSSI(indices[i]));
+            WiFi.SSID(indices[i]).c_str(), WiFi.BSSIDstr(indices[i]).c_str(), WiFi.channel(indices[i]), rssi);
-          int quality = WifiGetRssiAsQuality(WiFi.RSSI(indices[i]));
+          int quality = WifiGetRssiAsQuality(rssi);
           int auth = WiFi.encryptionType(indices[i]);
           char encryption[20];
           WSContentSend_P(PSTR("<div><a href='#p' onclick='c(this)'>%s</a>&nbsp;(%d)&nbsp<span class='q'>%s %d%% (%d dBm)</span></div>"),
             HtmlEscape(WiFi.SSID(indices[i])).c_str(),
             WiFi.channel(indices[i]),
             GetTextIndexed(encryption, sizeof(encryption), auth +1, kEncryptionType),
-            quality, WiFi.RSSI(indices[i])
+            quality, rssi
           );
           delay(0);
 
@@ -2067,7 +2068,8 @@ void HandleInformation(void)
     WSContentSend_P(PSTR("}1" D_FRIENDLY_NAME " %d}2%s"), i +1, SettingsText(SET_FRIENDLYNAME1 +i));
   }
   WSContentSend_P(PSTR("}1}2&nbsp;"));  // Empty line
-  WSContentSend_P(PSTR("}1" D_AP "%d " D_SSID " (" D_RSSI ")}2%s (%d%%, %d dBm)"), Settings.sta_active +1, SettingsText(SET_STASSID1 + Settings.sta_active), WifiGetRssiAsQuality(WiFi.RSSI()), WiFi.RSSI());
+  int32_t rssi = WiFi.RSSI();
+  WSContentSend_P(PSTR("}1" D_AP "%d " D_SSID " (" D_RSSI ")}2%s (%d%%, %d dBm)"), Settings.sta_active +1, SettingsText(SET_STASSID1 + Settings.sta_active), WifiGetRssiAsQuality(rssi), rssi);
   WSContentSend_P(PSTR("}1" D_HOSTNAME "}2%s%s"), my_hostname, (Wifi.mdns_begun) ? ".local" : "");
 #if LWIP_IPV6
     String ipv6_addr = WifiGetIPv6();