Intercooler water spray for ESP-32

iw_water_spray.ino

/*
  Intercooler Water Spray Controller  /  ZC33S
  ------------------------------------------------------------
  MCU      : ESP32 (Arduino core "ESP32 Dev Module")
  Boost in : AutoGauge 548 boost sensor WHITE wire (signal, ~1V @0bar)
             tapped via 1k series -> ADS1115 A0.  Sensor BLACK -> common GND.
             RED is left alone (the gauge powers the sensor). READ-ONLY: never
             drive voltage onto WHITE.
  Pump out : logic-level MOSFET low-side. Gate needs an external 10k pulldown
             to GND so the pump stays OFF whenever the MCU is unpowered.
             Flyback diode across the pump. Fuse (5-7.5A) on the pump 12V.
  LEDs     : RED  = hardware only, 5V rail -> 330ohm -> LED -> GND (power on/off)
             GREEN= GPIO -> 220ohm -> LED -> GND (lit while spraying; case A:
                    mirrors the pump, so it pulses with interval bursts)
  Master   : a toggle on the 12V(ACC) feed to the buck cuts MCU power = OFF.
             No software involvement; gate pulldown guarantees no spray.
  Config   : phone -> WiFi AP "ICWS-ZC33S" -> http://192.168.4.1
             Thresholds / interval / calibration are editable and persisted
             to NVS (survive power cycles). No logging.
  Libraries: Adafruit ADS1X15 (+ Adafruit BusIO). WiFi/WebServer/Preferences
             are part of the ESP32 core.
  ------------------------------------------------------------
  CALIBRATION (boost_bar = (mV - v0mV) / slopeMvBar):
    1) Key ON, engine OFF (manifold = atmosphere = 0 bar). Open the page,
       tap "Capture 0 bar" -> sets v0mV.
    2) Do a pull to a boost the AutoGauge gauge clearly shows (use its
       peak-recall). The page holds Peak mV. Then set slope by hand:
       slopeMvBar = (peakMv - v0mV) / peakBoost, type it into "slope",
       or while sitting at a known steady boost use "Capture slope point".
*/

#include <Wire.h>
#include <Adafruit_ADS1X15.h>
#include <WiFi.h>
#include <WebServer.h>
#include <Preferences.h>

// ---------- Pin map (ESP32) ----------
const int PIN_MOSFET    = 25;   // -> gate (EXTERNAL 10k pulldown to GND required)
const int PIN_LED_GREEN = 26;   // -> 220ohm -> green LED -> GND (spray active)
const int PIN_BTN       = 27;   // momentary push to GND (INPUT_PULLUP)
// I2C: SDA=21, SCL=22 -> ADS1115 (addr 0x48)

// ---------- WiFi AP ----------
const char* AP_SSID = "ICWS-ZC33S";
const char* AP_PASS = "spray12345";   // must be >= 8 chars

Adafruit_ADS1115 ads;
WebServer server(80);
Preferences prefs;

// ---------- Config (persisted in NVS) ----------
struct Config {
  float    boostOn;     // bar, arm threshold
  float    boostOff;    // bar, disarm threshold (hysteresis)
  uint32_t onMs;        // interval spray ON  (set offMs=0 for continuous)
  uint32_t offMs;       // interval spray OFF
  float    v0mV;        // white-wire mV at 0 bar (gauge)
  float    slopeMvBar;  // mV per bar
} cfg;

void loadCfg() {
  prefs.begin("icws", false);
  cfg.boostOn    = prefs.getFloat("boostOn", 0.40f);
  cfg.boostOff   = prefs.getFloat("boostOff", 0.20f);
  cfg.onMs       = prefs.getUInt ("onMs",    3000);
  cfg.offMs      = prefs.getUInt ("offMs",   1000);
  cfg.v0mV       = prefs.getFloat("v0mV",    456.2f);  // from screenshot; recalibrate with real sensor in car
  cfg.slopeMvBar = prefs.getFloat("slope",   456.2f);  // from screenshot; recalibrate with real sensor in car
  prefs.end();
}
void saveCfg() {
  prefs.begin("icws", false);
  prefs.putFloat("boostOn", cfg.boostOn);
  prefs.putFloat("boostOff", cfg.boostOff);
  prefs.putUInt ("onMs",    cfg.onMs);
  prefs.putUInt ("offMs",   cfg.offMs);
  prefs.putFloat("v0mV",    cfg.v0mV);
  prefs.putFloat("slope",   cfg.slopeMvBar);
  prefs.end();
}

// ---------- Runtime state ----------
bool  adsOk = false;
float lastMv = 0, lastBoost = 0, peakMv = 0;
bool  armed = false, sprayPhaseOn = true, spraying = false;
uint32_t lastPhase = 0, lastSample = 0;

float readMv() {
  if (!adsOk) return 0;
  int16_t raw = ads.readADC_SingleEnded(0);
  return ads.computeVolts(raw) * 1000.0f;
}
float toBoost(float mv) {
  if (cfg.slopeMvBar < 1.0f) return 0;
  return (mv - cfg.v0mV) / cfg.slopeMvBar;
}

// ---------- Web ----------
String page() {
  String s = F(
    "<!doctype html><html><head><meta charset=utf-8>"
    "<meta name=viewport content='width=device-width,initial-scale=1'>"
    "<title>ICWS</title><style>"
    "*{box-sizing:border-box}"
    "body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,sans-serif;"
    "margin:0;background:#0b0f14;color:#e6edf3;-webkit-font-smoothing:antialiased}"
    ".wrap{max-width:480px;margin:0 auto;padding:18px 14px 40px}"
    "header{display:flex;align-items:baseline;gap:10px;margin:6px 2px 16px}"
    ".logo{font-size:22px;font-weight:800;letter-spacing:.5px;"
    "background:linear-gradient(90deg,#22d3ee,#38bdf8);-webkit-background-clip:text;"
    "background-clip:text;-webkit-text-fill-color:transparent}"
    ".sub{font-size:11px;color:#7d8da1;text-transform:uppercase;letter-spacing:2px}"
    ".card{background:#11171f;border:1px solid #1e2733;border-radius:16px;padding:16px;margin-bottom:14px}"
    ".card h3{margin:0 0 10px;font-size:11px;letter-spacing:2px;text-transform:uppercase;color:#7d8da1;font-weight:600}"
    ".live{text-align:center}"
    ".status{display:inline-block;font-size:11px;font-weight:700;letter-spacing:2px;padding:4px 14px;border-radius:999px;margin-bottom:4px}"
    ".s-idle{background:#1b2430;color:#7d8da1}"
    ".s-armed{background:#3a2a06;color:#fbbf24}"
    ".s-spray{background:#06363f;color:#22d3ee;animation:pulse 1s infinite}"
    "@keyframes pulse{0%,100%{opacity:1}50%{opacity:.4}}"
    ".boost{font-size:54px;font-weight:800;line-height:1;margin:6px 0;font-variant-numeric:tabular-nums}"
    ".boost .unit{font-size:18px;color:#7d8da1;font-weight:600;margin-left:6px}"
    ".bar{position:relative;height:10px;background:#1b2430;border-radius:999px;margin:14px 0 10px;overflow:hidden}"
    ".fill{position:absolute;left:0;top:0;bottom:0;width:0;border-radius:999px;transition:width .25s ease}"
    ".fill.s-idle{background:#475569}.fill.s-armed{background:#f59e0b}"
    ".fill.s-spray{background:linear-gradient(90deg,#22d3ee,#38bdf8)}"
    ".mark{position:absolute;top:-3px;width:2px;height:16px;background:#e6edf3;opacity:.55}"
    ".meta{display:flex;justify-content:space-between;font-size:13px;color:#9fb0c3}"
    ".meta b{color:#e6edf3}"
    "label{display:flex;align-items:center;justify-content:space-between;gap:10px;font-size:14px;padding:9px 0;border-bottom:1px solid #161d27}"
    "label:last-child{border-bottom:0}"
    ".ig{display:flex;align-items:center;gap:8px}"
    ".u{color:#7d8da1;font-size:12px}"
    "input{background:#0b0f14;border:1px solid #28323f;color:#e6edf3;border-radius:10px;padding:9px 11px;width:96px;font-size:15px;text-align:right;font-variant-numeric:tabular-nums}"
    "input:focus{outline:none;border-color:#22d3ee;box-shadow:0 0 0 3px rgba(34,211,238,.15)}"
    "button{font-family:inherit;cursor:pointer;border:0;border-radius:11px;padding:11px 14px;font-size:14px;font-weight:600}"
    ".primary{width:100%;background:linear-gradient(90deg,#22d3ee,#38bdf8);color:#04121a;font-weight:800;letter-spacing:.5px}"
    ".ghost{background:transparent;border:1px solid #28323f;color:#9fb0c3;margin-top:12px}"
    ".cap{background:#1b2430;color:#e6edf3;border:1px solid #28323f}"
    ".full{width:100%}"
    ".row{display:flex;gap:8px;align-items:center}"
    ".row input{width:64px}.row button{flex:1}"
    "form{margin:0}"
    "</style></head><body><div class=wrap>"
    "<header><div class=logo>&#9889; ICWS</div><div class=sub>ZC33S&nbsp;Water&nbsp;Spray</div></header>"
    "<section class='card live'>"
    "<div class=status id=status>--</div>"
    "<div class=boost><span id=boost>--</span><span class=unit>bar</span></div>"
    "<div class=bar><div class=fill id=fill></div><div class=mark id=mark></div></div>"
    "<div class=meta><span id=mv>-- mV</span><span>Peak <b id=peak>--</b> mV</span></div>"
    "<form method=POST action=/resetpk><button class=ghost>reset peak</button></form>"
    "</section>"
    "<form method=POST action=/set>"
    "<section class=card><h3>Thresholds</h3>");
  s += "<label><span>Boost ON</span><span class=ig><input name=boostOn value=" + String(cfg.boostOn,2) + "><span class=u>bar</span></span></label>";
  s += "<label><span>Boost OFF</span><span class=ig><input name=boostOff value=" + String(cfg.boostOff,2) + "><span class=u>bar</span></span></label>";
  s += "<label><span>Spray ON</span><span class=ig><input name=onMs value=" + String(cfg.onMs) + "><span class=u>ms</span></span></label>";
  s += "<label><span>Spray OFF</span><span class=ig><input name=offMs value=" + String(cfg.offMs) + "><span class=u>ms</span></span></label>";
  s += F("</section><section class=card><h3>Calibration</h3>");
  s += "<label><span>v0 @0&nbsp;bar</span><span class=ig><input name=v0mV value=" + String(cfg.v0mV,1) + "><span class=u>mV</span></span></label>";
  s += "<label><span>slope</span><span class=ig><input name=slope value=" + String(cfg.slopeMvBar,1) + "><span class=u>mV/bar</span></span></label>";
  s += F("</section><button class=primary type=submit>Save</button></form>"
    "<section class=card><h3>Quick Calibrate</h3>"
    "<form method=POST action=/zero><button class='cap full'>Capture 0&nbsp;bar &middot; set v0 = now</button></form>"
    "<form method=POST action=/cal class=row style='margin-top:10px'>"
    "<span class=u>known</span><input name=kb value=1.0><span class=u>bar</span>"
    "<button class=cap>Capture slope</button></form>"
    "</section>"
    "<script>var ON=");
  s += String(cfg.boostOn,2);
  s += F(";function pct(b){var lo=-1.0,hi=2.0,p=(b-lo)/(hi-lo)*100;return Math.max(0,Math.min(100,p));}"
    "document.getElementById('mark').style.left=pct(ON)+'%';"
    "setInterval(function(){fetch('/live').then(r=>r.json()).then(j=>{"
    "document.getElementById('boost').textContent=j.boost.toFixed(2);"
    "document.getElementById('mv').textContent=j.mv.toFixed(0)+' mV';"
    "document.getElementById('peak').textContent=j.peak.toFixed(0);"
    "var c=j.spray?'s-spray':(j.armed?'s-armed':'s-idle');"
    "var st=document.getElementById('status');"
    "st.textContent=j.spray?'SPRAY':(j.armed?'ARMED':'IDLE');st.className='status '+c;"
    "var f=document.getElementById('fill');f.style.width=pct(j.boost)+'%';f.className='fill '+c;"
    "}).catch(e=>{});},250);"
    "</script></div></body></html>");
  return s;
}

void handleRoot() { server.send(200, "text/html", page()); }
void handleLive() {
  String j = "{\"mv\":" + String(lastMv,1) + ",\"boost\":" + String(lastBoost,3)
           + ",\"peak\":" + String(peakMv,1)
           + ",\"armed\":" + (armed ? "true" : "false")
           + ",\"spray\":" + (spraying ? "true" : "false") + "}";
  server.send(200, "application/json", j);
}
float argF(const char* n, float d) { return server.hasArg(n) ? server.arg(n).toFloat() : d; }

void handleSet() {
  cfg.boostOn    = argF("boostOn", cfg.boostOn);
  cfg.boostOff   = argF("boostOff", cfg.boostOff);
  cfg.onMs       = (uint32_t)argF("onMs", cfg.onMs);
  cfg.offMs      = (uint32_t)argF("offMs", cfg.offMs);
  cfg.v0mV       = argF("v0mV", cfg.v0mV);
  cfg.slopeMvBar = argF("slope", cfg.slopeMvBar);
  if (cfg.boostOff > cfg.boostOn) cfg.boostOff = cfg.boostOn;  // keep hysteresis sane
  saveCfg();
  server.sendHeader("Location", "/"); server.send(303, "text/plain", "");
}
void handleZero() {
  cfg.v0mV = readMv(); saveCfg();
  server.sendHeader("Location", "/"); server.send(303, "text/plain", "");
}
void handleCal() {
  float kb = argF("kb", 0);
  if (kb > 0.05f) {
    float sl = (readMv() - cfg.v0mV) / kb;
    if (sl > 100.0f) { cfg.slopeMvBar = sl; saveCfg(); }
  }
  server.sendHeader("Location", "/"); server.send(303, "text/plain", "");
}
void handleResetPk() {
  peakMv = lastMv;
  server.sendHeader("Location", "/"); server.send(303, "text/plain", "");
}

void setup() {
  Serial.begin(115200);
  pinMode(PIN_MOSFET, OUTPUT);    digitalWrite(PIN_MOSFET, LOW);
  pinMode(PIN_LED_GREEN, OUTPUT); digitalWrite(PIN_LED_GREEN, LOW);
  pinMode(PIN_BTN, INPUT_PULLUP);

  loadCfg();

  Wire.begin(21, 22);
  adsOk = ads.begin();                       // ADS1115 @ 0x48
  if (adsOk) ads.setGain(GAIN_TWOTHIRDS);    // +-6.144V (headroom; add divider if signal nears 5V)
  else       Serial.println("ADS1115 not found");

  WiFi.mode(WIFI_AP);
  WiFi.softAP(AP_SSID, AP_PASS);
  WiFi.setTxPower(WIFI_POWER_8_5dBm);   // 約8.5dBm ≈ 最大出力の約10%
  server.on("/",        handleRoot);
  server.on("/live",    handleLive);
  server.on("/set",     HTTP_POST, handleSet);
  server.on("/zero",    HTTP_POST, handleZero);
  server.on("/cal",     HTTP_POST, handleCal);
  server.on("/resetpk", HTTP_POST, handleResetPk);
  server.begin();
}

void loop() {
  server.handleClient();
  uint32_t now = millis();

  if (now - lastSample >= 20) {            // sample ~50 Hz
    lastSample = now;
    lastMv    = readMv();
    lastBoost = toBoost(lastMv);
    if (lastMv > peakMv) peakMv = lastMv;

    if      (lastBoost >= cfg.boostOn)  armed = true;    // hysteresis
    else if (lastBoost <= cfg.boostOff) armed = false;
  }

  if (armed) {                             // interval duty machine
    if ( sprayPhaseOn && (now - lastPhase >= cfg.onMs))  { sprayPhaseOn = false; lastPhase = now; }
    if (!sprayPhaseOn && (now - lastPhase >= cfg.offMs)) { sprayPhaseOn = true;  lastPhase = now; }
  } else {
    sprayPhaseOn = true; lastPhase = now;  // next arm starts on a spray burst
  }

  bool autoSpray = armed && sprayPhaseOn;
  bool manual    = (digitalRead(PIN_BTN) == LOW);   // held = force spray, ignores boost
  spraying = autoSpray || manual;

  digitalWrite(PIN_MOSFET,    spraying ? HIGH : LOW);
  digitalWrite(PIN_LED_GREEN, spraying ? HIGH : LOW);   // case A: green mirrors the pump
}