wt32powermeter.ino gelöscht

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Michael Clemens // DK1MI 2024-03-04 12:51:17 +00:00
parent 0c81ab67d2
commit 0b3b240366
1 changed files with 0 additions and 725 deletions

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/****************************************************************************************************************************
Remote Power/SWR Meter - a solution to remotely measure RF power and VSWR over ethernet
For Ethernet shields using WT32_ETH01 (ESP32 + LAN8720)
Uses WebServer_WT32_ETH01, a library for the Ethernet LAN8720 in WT32_ETH01 to run WebServer
Author: Michael Clemens, DK1MI
Licensed under GPLv3 license (see LICENSE.md)
VU meter code was taken from https://github.com/tomnomnom/vumeter, credits go to Tom Hudson (https://github.com/tomnomnom)
*****************************************************************************************************************************/
#define DEBUG_ETHERNET_WEBSERVER_PORT Serial
// Debug Level from 0 to 4
#define _ETHERNET_WEBSERVER_LOGLEVEL_ 3
#define FORMAT_SPIFFS_IF_FAILED true
#include <WebServer_WT32_ETH01.h>
#include "javascript.h"
#include "dashboard_css.h"
#include "config_css.h"
#include "index.h" // Main Web page header file
#include <Preferences.h>
#include "FS.h"
#include "SPIFFS.h"
#include <OneWire.h>
#include <DallasTemperature.h>
String version = "1.0.2";
Preferences config;
Preferences global_config;
String band_config_items[] = { "b_show_mV", "b_show_dBm", "b_show_watt", "s_vswr_thresh", "b_vswr_beep", "s_ant_name", "s_max_led_pwr_f", "s_max_led_pwr_r", "s_max_led_vswr", "b_show_led_fwd", "b_show_led_ref", "b_show_led_vswr", "s_cable_loss", "b_power_avg", "b_show_temp", "b_celsius" };
String band_config_defaults[] = { "true", "true", "true", "2", "true", " ", "100", "100", "3", "true", "true", "true", "0", "false", "false", "true" };
String band_config_nice_names[] = { "Show voltage in mV (yes/no)", "Show power level in dBm (yes/no)", "Show power in Watt (yes/no)", "VSWR threshold that triggers a warning (e.g. 3)", "Beep if VSWR threshold is exceeded (yes/no)", "Name of the antenna", "Max. FWD power displayed by LED bar graph in W (e.g. 100)", "Max. REF power displayed by LED bar graph in W (e.g. 100)", "Max. VSWR displayed by LED bar graph (e.g. 3)", "Show LED graph for FWD power (yes/no)", "Show LED graph for REF power (yes/no)", "Show LED graph for VSWR (yes/no)","Cable loss in db (e.g. 3)","Display average power instead of PEP? (yes=AVG/no=PEP)", "Display Temperature? (yes/no)", "Display Temperature in C or F? (yes=C/no=F)" };
double fwd_array[3300] = {};
double ref_array[3300] = {};
int voltage_fwd, voltage_ref;
double fwd_dbm = 0, ref_dbm = 0;
double fwd_watt = 0, ref_watt = 0;
byte iii = 0;
String conf_content;
String conf_textareas = "";
String conf_config_table = "";
String band = "";
String default_band = "70cm";
String band_fwd = band + "_fwd";
String band_ref = band + "_ref";
String band_list[] = { "1.25cm", "3cm", "6cm", "9cm", "13cm", "23cm", "70cm", "2m", "HF" };
int IO2_FWD = 2;
int IO4_REF = 4;
const int IO14_TEMP = 14;
OneWire oneWire(IO14_TEMP);
DallasTemperature sensors(&oneWire);
WebServer server(80);
// Select the IP address according to your local network
IPAddress myIP(192, 168, 1, 100);
IPAddress myGW(192, 168, 1, 1);
IPAddress mySN(255, 255, 255, 0);
IPAddress myDNS(192, 168, 1, 1);
// Reads a file from SPIFF and returns its content as a string
String readFile(fs::FS &fs, const char *path) {
Serial.printf("Reading file: %s\r\n", path);
File file = fs.open(path);
if (!file || file.isDirectory()) {
Serial.println("failed to open file for reading");
return "";
}
String ret = "";
Serial.println("read from file:");
while (file.available()) {
ret += char(file.read());
}
file.close();
return ret;
}
// Takes a string and writes it to a file on SPIFF
void writeFile(fs::FS &fs, const char *path, const char *message) {
Serial.printf("Writing file: %s\r\n", path);
File file = fs.open(path, FILE_WRITE);
if (!file) {
Serial.println("failed to open file for writing");
return;
}
if (file.print(message)) {
Serial.println("file written");
} else {
Serial.println("file write failed");
}
file.close();
}
// converts dBm to Watt
double dbm_to_watt(double dbm) {
return pow(10.0, (dbm - 30.0) / 10.0);
}
// checks if a given voltage is lower as the smallest value
// in the table or higher than the biggest value
bool is_val_out_of_bounds(int mv, bool fwd) {
double stored_val = 0;
int key_a = 0;
int key_b = 0;
// searches for the first key (voltage) that has a value (dBm)
for (int i = 0; i < 3300; i++) {
if (fwd) {
stored_val = fwd_array[i];
} else {
stored_val = ref_array[i];
}
if (stored_val != 0) {
key_a = i;
break;
}
}
// searches for the last key (voltage) that has a value (dBm)
for (int i = 3299; i > 0; i--) {
if (fwd) {
stored_val = fwd_array[i];
} else {
stored_val = ref_array[i];
}
if (stored_val != 0) {
key_b = i;
break;
}
}
int lowerkey = min(key_a, key_b); // takes both values found above and assigns the lower key
int higherkey = max(key_a, key_b); // takes both values found above and assigns the higher key
// returns false if given voltage is between the lowest and highest configured voltages
// returns true if voltage is out of bounds
if (lowerkey <= mv and mv <= higherkey)
return false;
else {
return true;
}
}
// takes a voltage value and translates it
// to dBm based on the corresponding lookup table
double millivolt_to_dbm(int mv, bool fwd) {
double lastval = 0;
double nextval = 0;
int lastkey = 0;
int nextkey = 0;
double stored_val = 0;
bool ascending = true;
int lowest_key_in_table = 0;
int highest_key_in_table = 0;
// check if table is ascending or descending
double asc_tmp_val = 0;
for (int i = 0; i < 3300; i++) {
if (fwd) {
stored_val = fwd_array[i];
} else {
stored_val = ref_array[i];
}
if (stored_val != 0) {
if (asc_tmp_val == 0) {
asc_tmp_val = stored_val;
} else if (stored_val > asc_tmp_val) {
ascending = true;
break;
} else if (stored_val < asc_tmp_val) {
ascending = false;
break;
}
}
}
// checks if the voltage values are opposite to the dBm values or
// if both, voltage and dBm values are ascending
if (ascending) {
for (int i = 0; i < 3300; i++) {
if (fwd) {
stored_val = fwd_array[i];
} else {
stored_val = ref_array[i];
}
if (stored_val != 0) {
if (lowest_key_in_table == 0) {
lowest_key_in_table = i; //finds the lowest voltage value stored in the table
}
highest_key_in_table = i; // we will have the highest voltage value in the table at the end of the loop
if (i < mv) {
lastval = stored_val;
lastkey = i;
} else {
nextval = stored_val;
nextkey = i;
break;
}
}
}
} else {
for (int i = 3300; i > 0; i--) {
if (fwd) {
stored_val = fwd_array[i];
} else {
stored_val = ref_array[i];
}
if (stored_val != 0) {
if (lowest_key_in_table == 0) {
lowest_key_in_table = i; //finds the lowest voltage value stored in the table
}
highest_key_in_table = i; // we will have the highest voltage value in the table at the end of the loop
if (i > mv) {
lastval = stored_val;
lastkey = i;
} else {
nextval = stored_val;
nextkey = i;
break;
}
}
}
}
double lowerkey = min(lastkey, nextkey);
double higherkey = max(lastkey, nextkey);
double lowerval = min(lastval, nextval);
double higherval = max(lastval, nextval);
double diffkey = max(lastkey, nextkey) - min(lastkey, nextkey);
double diffval = max(lastval, nextval) - min(lastval, nextval);
double result = 0;
if (ascending) {
result = lowerval + ((diffval / diffkey) * (mv - lowerkey));
} else {
result = higherval - ((diffval / diffkey) * (mv - lowerkey));
}
return result;
}
// read voltages from both input pins
// calculates avaerage value of 50 measurements
void read_directional_couplers() {
int voltage_sum_fwd = 0;
int voltage_sum_ref = 0;
int voltage_fwd_max = 0;
int voltage_ref_max = 0;
int voltage_fwd_now = 0;
int voltage_ref_now = 0;
// Takes 50 samples and sums them up
// figure out the highest values
for (iii = 0; iii < 50; iii++) {
voltage_fwd_now = analogReadMilliVolts(IO2_FWD);
voltage_ref_now = analogReadMilliVolts(IO4_REF);
voltage_sum_fwd += voltage_fwd_now;
voltage_sum_ref += voltage_ref_now;
voltage_fwd_max = max(voltage_fwd_now, voltage_fwd_max);
voltage_ref_max = max(voltage_ref_now, voltage_ref_max);
}
if (config.getString(String("s_power_avg").c_str()) == "true") {
// calculate the average value by deviding the above sum by 50
voltage_fwd = voltage_sum_fwd / 50;
voltage_ref = voltage_sum_ref / 50;
} else {
// take the highest value of the 50 samples
voltage_fwd = voltage_fwd_max;
voltage_ref = voltage_ref_max;
}
// calculate the dBm value from the voltage based on the calibration table
fwd_dbm = millivolt_to_dbm(voltage_fwd, true);
ref_dbm = millivolt_to_dbm(voltage_ref, false);
// add cable loss to FWD dBm, substract cable loss from REF dBm
double cable_loss = 0;
cable_loss = config.getString(String("s_cable_loss").c_str()).toDouble();
//Serial.println("cable loss: " + String(cable_loss));
fwd_dbm = fwd_dbm - cable_loss;
ref_dbm = ref_dbm + cable_loss;
// calculate watt from dBm
fwd_watt = dbm_to_watt(fwd_dbm);
ref_watt = dbm_to_watt(ref_dbm);
}
// delivers the dashboard page in "index.h"
void handleRoot() {
String html = MAIN_page;
String css = DB_STYLESHEET;
String js = JAVASCRIPT;
server.send(200, "text/html", css + js + html);
}
// delivers a 404 page if a non-existant resouurce is requested
void handleNotFound() {
String message = F("File Not Found\n\n");
message += F("URI: ");
message += server.uri();
message += F("\nMethod: ");
message += (server.method() == HTTP_GET) ? F("GET") : F("POST");
message += F("\nArguments: ");
message += server.args();
message += F("\n");
for (uint8_t i = 0; i < server.args(); i++) {
message += " " + server.argName(i) + ": " + server.arg(i) + "\n";
}
server.send(404, F("text/plain"), message);
}
// executes the function to gather sensor data
// delivers gathered data to dashboard page
// invoked periodically by the dashboard page
void handleDATA() {
read_directional_couplers();
double vswr = 0;
if (fwd_watt > ref_watt) {
vswr = (1 + sqrt(ref_watt / fwd_watt)) / (1 - sqrt(ref_watt / fwd_watt));
}
String vswr_str = "-1";
String fwd_watt_str = "";
String ref_watt_str = "";
if (vswr >= 1) {
vswr_str = String(vswr);
}
double rl = fwd_dbm - ref_dbm;
// get vswr_threshold from general config
String vswr_threshold = config.getString(String("s_vswr_thresh").c_str());
String voltage_fwd_str = "";
String voltage_ref_str = "";
if (config.getString(String("b_show_mV").c_str()) != "false") {
voltage_fwd_str = String(voltage_fwd) + " mV";
voltage_ref_str = String(voltage_ref) + " mV";
}
String fwd_dbm_str = "";
String ref_dbm_str = "";
if (config.getString(String("b_show_dBm").c_str()) != "false") {
fwd_dbm_str = String(fwd_dbm, 2);
ref_dbm_str = String(ref_dbm, 2);
}
if (config.getString(String("b_show_watt").c_str()) != "false") {
fwd_watt_str = String(fwd_watt, 10);
}
if (config.getString(String("b_show_watt").c_str()) != "false") {
ref_watt_str = String(ref_watt, 10);
}
String rl_str = "-- ";
if (rl > 0) {
rl_str = (String(rl));
}
rl_str.replace("nan", "-- ");
String antenna_name = config.getString(String("s_ant_name").c_str());
String vswr_beep = config.getString(String("b_vswr_beep").c_str());
bool fwd_oob = is_val_out_of_bounds(voltage_fwd, true);
bool ref_oob = is_val_out_of_bounds(voltage_ref, false);
// Generate a semicolon seperated string that will be sent to the frontend
String output = fwd_watt_str + ";"; // data[0]: FWD power in Watt
output += fwd_dbm_str + ";"; // data[1]: FWD dBm value
output += voltage_fwd_str + ";"; // data[2]: FWD voltage
output += ref_watt_str + ";"; // data[3]: REF power in Watt
output += ref_dbm_str + ";"; // data[4]: REF dBm value
output += voltage_ref_str + ";"; // data[5]: REF voltage
output += vswr_str + ";"; // data[6]: VSWR value
output += rl_str + ";"; // data[7]: RL value
output += band + ";"; // data[8]: band (e.g. "70cm")
output += String(vswr_threshold) + ";"; // data[9]: VSWR threshold (e.g. "3")
output += antenna_name + ";"; // data[10]: Name of antenna (e.g. "X200")
output += vswr_beep + ";"; // data[11]: should it beep if VSWR is too high? (true/false)
output += config.getString(String("s_max_led_pwr_f").c_str()) + ";"; // data[12]: highest value in Watt for the FWD LED graph (e.g. "100")
output += config.getString(String("s_max_led_pwr_r").c_str()) + ";"; // data[13]: highest value in Watt for the REF LED graph (e.g. "1")
output += config.getString(String("s_max_led_vswr").c_str()) + ";"; // data[14]: highest value in Watt for the VSWR LED graph (e.g. "3")
output += String(fwd_oob) + ";"; // data[15]: Is the FWD voltage out of bounds? (true/false)
output += String(ref_oob) + ";"; // data[16]: Is the REF voltage out of bounds? (true/false)
output += config.getString(String("b_show_led_fwd").c_str()) + ";"; // data[17]: Show the FWD LED bar graph? (true/false)
output += config.getString(String("b_show_led_ref").c_str()) + ";"; // data[18]: Show the REF LED bar graph? (true/false)
output += config.getString(String("b_show_led_vswr").c_str()) + ";"; // data[19]: Show the VSWR LED bar graph? (true/false)
output += version + ";"; // data[20]: program version
output += getTemp(); // data[21]: temperature
server.send(200, "text/plane", output);
}
// main function for displaying the configuration page
// invoked by the "configuration" button on the dashboard page
void handleCONFIG() {
if (conf_textareas == "") {
build_textareas();
}
if (conf_config_table == "") {
build_config_table();
}
String css = CFG_STYLESHEET;
conf_content = css;
conf_content += "<div class='grid-container'>";
conf_content += "<div id='title_box' class='titlebox maintitlebox'>";
conf_content += "Configuration</div>";
conf_content += "<div id='title_box' class='bandbox maintitlebox'>";
conf_content += "<form method='POST' action='/selectband'>";
conf_content += "Band: <label for='bands'></label><select class='button' onchange='this.form.submit()'' id='band' name='bands' size='1'>";
for (int i = 0; i < sizeof band_list / sizeof band_list[0]; i++) {
String selected = "";
if (band_list[i] == band) {
selected = "selected";
}
conf_content += "<option value='" + band_list[i] + "' " + selected + " >" + band_list[i] + "</option>";
}
conf_content += "</select></form>";
conf_content += "</div>";
conf_content += "<div class='subtitle1 subtitlebox'>Translation Detector Voltage /mV to RF-Power Level /dBm</div>";
conf_content += "<div class='translationitems contentbox'>";
conf_content += conf_textareas;
conf_content += "</div>";
conf_content += "<div class='subtitle2 subtitlebox'>General Configuration Items</div>";
conf_content += "<div class='configitems contentbox'>";
conf_content += conf_config_table;
conf_content += "</div>";
conf_content += "<div class='footerbox'>";
conf_content += "<form method='POST' action='/'><button class='linkbutton' value='back' name='back' type='submit'>Back to Dashboard</button> - Version: " + version + " </form>";
conf_content += "</div>";
conf_content += "</div>";
conf_content += "</html>";
server.send(200, "text/html", conf_content);
}
// generates the translation table for either the FWD or
// REF values
void build_textareas() {
String fwd = readFile(SPIFFS, String("/" + band + "fwd.txt").c_str());
String ref = readFile(SPIFFS, String("/" + band + "ref.txt").c_str());
clear_fwd_ref_array();
save_string_to_array(fwd, fwd_array);
save_string_to_array(ref, ref_array);
String tbl = "<form action=\"/modcal\" method=\"POST\">";
tbl += "<table class='styled-table'>";
tbl += "<thead><tr><td>" + band + " FWD (mV:dBm)</td><td>" + band + " REF (mV:dBm)</td></tr></thead>";
tbl += "<tr><td>";
tbl += "<textarea id='fwd_textarea' name='fwd_textarea' rows='22'>";
for (int i = 0; i < sizeof fwd_array / sizeof fwd_array[0]; i++) {
if (fwd_array[i] != 0) {
tbl += String(i) + ":" + String(fwd_array[i], 5) + "\n";
}
}
tbl += "</textarea>";
tbl += "</td><td>";
tbl += "<textarea id='ref_textarea' name='ref_textarea' rows='22'>";
for (int i = 0; i < sizeof ref_array / sizeof ref_array[0]; i++) {
if (ref_array[i] != 0) {
tbl += String(i) + ":" + String(ref_array[i], 5) + "\n";
}
}
tbl += "</textarea>";
tbl += "</td></tr></table>";
tbl += "<button class='button' value='save' name='save' type='submit'>Save Calibration Data</button>";
tbl += "</form>";
conf_textareas = tbl;
}
// generates the table with generic configuration items
void build_config_table() {
conf_config_table = "<form action=\"/modcfg\" method=\"POST\">";
conf_config_table += "<table class='styled-table'>";
//conf_config_table += "<thead><tr><td>Key</td><td>Value</td></td></tr></thead>";
for (int i = 0; i < sizeof band_config_items / sizeof band_config_items[0]; i++) {
if (!band_config_items[i].startsWith("x_")) {
String stored_val = config.getString(band_config_items[i].c_str(), "xxx");
if (stored_val == "xxx") {
config.putString(band_config_items[i].c_str(), band_config_defaults[i]);
stored_val = config.getString(band_config_items[i].c_str(), "");
}
conf_config_table += "<tr><td>";
conf_config_table += band_config_nice_names[i];
conf_config_table += "</td><td>";
if (String(stored_val).equalsIgnoreCase("true")) {
conf_config_table += "<input type='checkbox' name='" + band_config_items[i] + "' id='" + band_config_items[i] + "' value='true' checked>";
} else if (String(stored_val).equalsIgnoreCase("false")) {
conf_config_table += "<input type='checkbox' name='" + band_config_items[i] + "' id='" + band_config_items[i] + "' value='false'>";
} else {
conf_config_table += "<input name='" + band_config_items[i] + "' value='" + String(stored_val) + "' valuelength=16>";
}
conf_config_table += "</td></tr>";
}
}
conf_config_table += "</table><button class='button' value='save' name='save' type='submit'>Save Configuration</button></form>";
handleCONFIG();
}
// Handle request from the config page to change or add values
// to the XXXX value table for the selected band
void handleMODCAL() {
String fwd = server.arg("fwd_textarea") + "\n";
String ref = server.arg("ref_textarea") + "\n";
clear_fwd_ref_array();
save_string_to_array(fwd, fwd_array);
save_string_to_array(ref, ref_array);
String fwd_of_array = "";
for (int i = 0; i < sizeof fwd_array / sizeof fwd_array[0]; i++) {
if (fwd_array[i] != 0) {
fwd_of_array += String(i) + ":" + String(fwd_array[i], 5) + "\n";
}
}
writeFile(SPIFFS, String("/" + band + "fwd.txt").c_str(), fwd_of_array.c_str());
String ref_of_array = "";
for (int i = 0; i < sizeof ref_array / sizeof ref_array[0]; i++) {
if (ref_array[i] != 0) {
ref_of_array += String(i) + ":" + String(ref_array[i], 5) + "\n";
}
}
writeFile(SPIFFS, String("/" + band + "ref.txt").c_str(), ref_of_array.c_str());
build_textareas();
handleCONFIG();
}
// resets all vlaues in the FWD and REF array
void clear_fwd_ref_array() {
for (int x = 0; x < sizeof(fwd_array) / sizeof(fwd_array[0]); x++) {
fwd_array[x] = 0;
ref_array[x] = 0;
}
}
// after the user edited the calibration table via the frontend,
// this function takes the resulting string, detonates it and
// writes all rows into an array
void save_string_to_array(String table_data, double arr[]) {
int r = 0, t = 0;
for (int i = 0; i < table_data.length(); i++) {
if (table_data[i] == '\n' || i == table_data.length()) {
if (i - r > 1) {
String row = table_data.substring(r, i);
t++;
int r2 = 0, t2 = 0;
for (int j = 0; j < row.length(); j++) {
if (row[j] == ':' || row[j] == '\n') {
if (j - r2 > 1) {
int key = row.substring(r2, j).toInt();
double val = row.substring(j + 1).toDouble();
arr[key] = val;
t2++;
}
r2 = (j + 1);
}
}
}
r = (i + 1);
}
}
}
// Handle request from the config page to change or add values
// to the general config value table for the selected band
void handleMODCFG() {
for (int i = 0; i < sizeof band_config_items / sizeof band_config_items[0]; i++) {
if (!server.hasArg(band_config_items[i]) and band_config_items[i].startsWith("b_")) {
config.putString(band_config_items[i].c_str(), "false");
} else if (server.hasArg(band_config_items[i]) and band_config_items[i].startsWith("b_")) {
config.putString(band_config_items[i].c_str(), "true");
} else {
config.putString(band_config_items[i].c_str(), server.arg(band_config_items[i]));
}
}
conf_config_table = "";
build_config_table();
}
// changes the band according to the user's selection
// regenerates the calibration tables and fills them
// with the values assigned to the respective band
// invoked by selecting a band from the select box of the config page
void handleBAND() {
band = server.arg("bands");
band_fwd = band + "_fwd";
band_ref = band + "_ref";
global_config.putString(String("x_selected_band").c_str(), band);
config.end();
String bnd_cnf = "config_" + band;
config.begin(bnd_cnf.c_str(), false);
conf_textareas = "";
conf_config_table = "";
//build_config_table();
//build_textareas();
handleCONFIG();
}
// reads the temperature from the aboce defined sensor
// and returns it in either C or F as a string
String getTemp() {
String ret = "";
if (config.getString(String("b_show_temp").c_str()) == "true") {
String label = "Temp: ";
String temp_string = "--";
String unit = "";
float temp_float;
sensors.requestTemperatures();
if (config.getString(String("b_celsius").c_str()) != "false") {
unit = "°C";
temp_float = sensors.getTempCByIndex(0);
} else {
unit = "°F";
temp_float = sensors.getTempFByIndex(0);
}
if (temp_float > -100){
temp_string = String(temp_float, 1);
}
ret = label + temp_string + unit;
}
return ret;
}
// initialization routine
void setup() {
Serial.begin(115200);
// initialize temperature sensor
sensors.begin();
Serial.print("\nStarting AdvancedWebServer on " + String(ARDUINO_BOARD));
Serial.println(" with " + String(SHIELD_TYPE));
Serial.println(WEBSERVER_WT32_ETH01_VERSION);
// To be called before ETH.begin()
WT32_ETH01_onEvent();
ETH.begin(ETH_PHY_ADDR, ETH_PHY_POWER);
// Static IP, leave without this line to get IP via DHCP
//ETH.config(myIP, myGW, mySN, myDNS);
WT32_ETH01_waitForConnect();
// activates single web server endpoints
server.on(F("/"), handleRoot);
server.on("/readDATA", handleDATA);
server.on("/config", handleCONFIG);
server.on("/modcfg", handleMODCFG);
server.on("/selectband", handleBAND);
server.on("/modcal", handleMODCAL);
if (!SPIFFS.begin(FORMAT_SPIFFS_IF_FAILED)) {
Serial.println("SPIFFS Mount Failed");
return;
}
server.onNotFound(handleNotFound);
server.begin();
Serial.print(F("HTTP EthernetWebServer is @ IP : "));
Serial.println(ETH.localIP());
analogReadResolution(12);
global_config.begin("config", false);
band = global_config.getString(String("x_selected_band").c_str());
if (band == "") {
global_config.putString(String("x_selected_band").c_str(), default_band);
band = default_band;
}
String bnd_cnf = "config_" + band;
config.begin(bnd_cnf.c_str(), false);
build_textareas();
}
void loop() {
server.handleClient();
}