got parameter fetch working beta only

data/input.js

     },
     body: ''
   })
-    .then(response => response.text())
-    .then(data => {
-      if(data.length > 0) {
-        terminal.innerHTML += data;
-        if (autoscroll.checked)
-          terminal.scrollTop = terminal.scrollHeight;
-      }
-    })
-    .catch(error => console.log('Error:', error));
+  .then(response => response.text())
+  .then(data => {
+    if(data.length > 0) {
+      terminal.innerHTML += data;
+      if (autoscroll.checked)
+        terminal.scrollTop = terminal.scrollHeight;
+    }
+  })
+  .catch(error => console.log('Error:', error));
+};
+
+function updateParameters() {
+  fetch('/parameters', {
+    method: 'POST',
+    headers: {
+      'Content-Type': 'application/x-www-form-urlencoded',
+    },
+    body: ''
+  })
+  .then(response => response.json())
+  .then(json_str => {
+    const active_pwm = Math.round(json_str.active_pwm / 4095 * 100);
+    document.querySelector('#range_act_pwm').value = active_pwm;
+    document.querySelector('#out_act_pwm').value = active_pwm;
+    
+    const idle_pwm_max = Math.round(json_str.idle_pwm_max / json_str.active_pwm * 100);
+    document.querySelector('#range_idl_pwm').value = idle_pwm_max;
+    document.querySelector('#out_idl_pwm').value = idle_pwm_max;
+
+    document.querySelector('#range_tim_sta').value = json_str.time_per_stair;
+    document.querySelector('#out_tim_sta').value = json_str.time_per_stair;
+
+    document.querySelector('#range_tim_ldr').value = json_str.time_ldr;
+    document.querySelector('#out_tim_ldr').value = json_str.time_ldr;
+
+    document.querySelector('#range_ldr_shw').value = json_str.ldr_schwelle;
+    document.querySelector('#out_ldr_shw').value = json_str.ldr_schwelle;
+
+  })
+  .catch(error => console.log('Error:', error));
 };
 
 document.addEventListener('DOMContentLoaded', () => {
   setInterval(reloadTerminal, 1000);
   setInterval(reloadRangeValues, 1000);
 
+  updateParameters();
 
   // use data- attributes for action
   document.querySelectorAll('.control').forEach((button) => {

lib/httpserver/httpserver.cpp

       send(202, "text/plain", "");
     }
   });
+
+  this->on("/parameters", HTTP_POST, [this]() {
+    logt("got /parameters\n");
+    char json_str[255];
+    treppe->param_to_json(json_str, 255);
+    logt("%s\n", json_str);
+    send(200, "application/json", json_str);
+  });
 }
 
 template <class... Args>

lib/treppe/treppe.cpp

       dimmer->stufe = stufen - 1;
 
     dimmer->ticks = param.time_per_stair / INT_TIME; // [ms]
-  } else {                                                // DIM_LDR
+  } else {                                           // DIM_LDR
     dimmer->ticks = param.time_ldr / INT_TIME;       // [ms]
   }
 
   E(LDR) = 6526.5 / (R(LDR)^2)
   ldr_value = E(LDR)
   */
-  //float ldr_ohm = 37280.00 / analogRead(A0);
-  float voltage = analogRead(A0)*0.0036;
-  float ldr_ohm = 40.57*(3.3-voltage)/voltage;
+  // float ldr_ohm = 37280.00 / analogRead(A0);
+  float voltage = analogRead(A0) * 0.0036;
+  float ldr_ohm = 40.57 * (3.3 - voltage) / voltage;
   float ldr_value = 6526.6 / (ldr_ohm * ldr_ohm);
-  #ifdef LDRDEBUG
-  Serial.printf("Ohm: %f lux: %f Comp: %d\n", ldr_ohm,ldr_value, param.ldr_schwelle);
-  #endif
+#ifdef LDRDEBUG
+  Serial.printf("Ohm: %f lux: %f Comp: %d\n", ldr_ohm, ldr_value,
+                param.ldr_schwelle);
+#endif
   return ldr_value;
 }
 
   static uint8_t active = 0;
 
 #ifdef LDRDEBUG
-  //return true;
+  // return true;
 #endif
 
   // follow up: averaging over many samples?
     if (!fsm_pend.anim_beendet) {
       fsm_pend.anim_beendet = dimmer_tick(&dimmer_ldr, DIM_LDR);
     }
-
   }
 
-  if (fsm_outputs.status == ST_RUHEZUSTAND || 
-      fsm_outputs.status == ST_INAKTIV_LDR){
-        if (param_changed) {
-          param_changed = false;
-          param = param_pend;
-          save_param_to_eeprom();
-          Serial.printf("Parameter Change applied!\n");
-        }
+  if (fsm_outputs.status == ST_RUHEZUSTAND ||
+      fsm_outputs.status == ST_INAKTIV_LDR) {
+    if (param_changed) {
+      param_changed = false;
+      param = param_pend;
+      save_param_to_eeprom();
+      Serial.printf("Parameter Change applied!\n");
+    }
   }
 
 #ifdef DEBUG_TIMING
 void Treppe::save_param_to_eeprom() {
   EEPROM.put(EEP_START_ADDR,
              param); // copy Parameters so "EEPROM"-section in RAM
-  EEPROM.commit();        // write "EEPROM"-section to flash
+  EEPROM.commit();   // write "EEPROM"-section to flash
 }
 
 void Treppe::set_idle_pwm_max(const uint16_t value,
     // ?!
     param_pend.ldr_schwelle = 10 * value / 100;
   } else if (vorgabe_typ == VORGABE_12BIT) {
-     param_pend.ldr_schwelle = value;
+    param_pend.ldr_schwelle = value;
   }
   param_changed = true;
 
   Serial.printf("Treppe: ldr_schwelle=%d\n", param_pend.ldr_schwelle);
+}
+
+void Treppe::param_to_json(char *json_str, size_t sz) {
+  snprintf(json_str, sz, "{\n\
+    \"time_ldr\": %d,\n\
+    \"time_per_stair\": %d,\n\
+    \"idle_pwm_max\": %d,\n\
+    \"active_pwm\": %d,\n\
+    \"ldr_schwelle\": %d\n}\n",
+           param.time_ldr, param.time_per_stair, param.idle_pwm_max,
+           param.active_pwm, param.ldr_schwelle);
 }

lib/treppe/treppe.h

 
   // Parameter section
   void save_param_to_eeprom();
+  void param_to_json(char* json_str, size_t sz);
+
   void set_idle_pwm_max(const uint16_t value, const vorgabe_typ_t vorgabe_typ);
   void set_active_pwm(const uint16_t value, const vorgabe_typ_t vorgabe_typ);