Persistent storage for wifi credentials

clockspot · clockspot · commit 02de84af2397 · 2021-03-12T12:29:21.000-06:00
diff --git a/README.md b/README.md
@@ -14,19 +14,19 @@ To see your clock’s software version, hold **Select** briefly while powering u
 
 **A universal digital clock codebase for Arduino,** maintained by [Luke](https://theclockspot.com).
 
-* Time of day with automatic DST change and chimes.
-* Perpetual calendar with day counter and local sunrise/sunset times.
-* Daily alarm with snooze and automatic weekday/weekend skipping.
-* Chronograph and timer with reset/interval options.
-* Simple control via three/four buttons, a rotary encoder, and/or an [IMU](https://en.wikipedia.org/wiki/Inertial_measurement_unit) (tilt control).
-* Signals via piezo beeper, switch (e.g. appliance timer), and/or pulse (e.g. bell ringer).
-* Supports Nixie displays of two SN74141 chips driving four/six tubes, with anti-cathode poisoning.
-* Supports LED displays of three/four MAX7219 chips (via SPI) driving 8x8 LED matrices ([example](https://www.amazon.com/HiLetgo-MAX7219-Arduino-Microcontroller-Display/dp/B07FFV537V/)).
-* Supports scheduled display dim/shutoff and switchable backlighting with optional PWM fade.
+* **Time of day** with automatic DST change and chimes.
+* **Perpetual calendar** with day counter and local sunrise/sunset times.
+* **Alarm** with snooze and automatic weekday/weekend skipping.
+* **Chronograph and timer** with reset/interval options.
+* Runs on both classic Arduino Nano (AVR) and Nano 33 IoT (SAMD21).
+* Supports **web-based config and NTP sync** over Wi-Fi on Nano 33 IoT.
+* **Simple control** via three/four buttons, a rotary encoder, and/or Nano 33 IoT’s [IMU](https://en.wikipedia.org/wiki/Inertial_measurement_unit) (tilt control).
+* **Signals** via piezo beeper, switch (e.g. appliance timer), and/or pulse (e.g. bell ringer).
+* Supports **Nixie displays** of two SN74141 chips driving four/six tubes, with anti-cathode poisoning.
+* Supports **LED displays** of three/four MAX7219 chips (via SPI) driving 8x8 LED matrices ([example](https://www.amazon.com/HiLetgo-MAX7219-Arduino-Microcontroller-Display/dp/B07FFV537V/)).
+* Scheduled nightly/weekly **display dim/shutoff** and switchable backlighting with optional PWM fade.
 * Timekeeping can be internal, or based on a DS3231 RTC (via I2C) for reliability/accuracy.
-* Supports both AVR and SAMD Arduinos (tested on Arduino Nano and Nano 33 IoT).
-* On Nano 33 IoT, supports web-based config and NTP sync over Wi-Fi.
-* User settings kept in persistent storage, but also mirrored in RAM in case of EEPROM/flash failure.
+* Settings stored persistently in case of power loss, and mirrored in RAM in case of EEPROM/flash failure.
 
 Written to support [RLB Designs’](http://rlb-designs.com/) Universal Nixie Driver Board (UNDB):
 
@@ -38,13 +38,13 @@ Written to support [RLB Designs’](http://rlb-designs.com/) Universal Nixie Dri
 
 # Configuration, compilation, and upload
 
-Various options, such as enabled functionality, RTC, display, I/O pins, timeouts, and control behaviors, are specified in a config file. This allows you to maintain configs for multiple clock hardware profiles, and simply include the relevant config at the top of the `.ino` before compiling. Several [example configs](https://github.com/clockspot/arduino-clock/tree/master/arduino-clock/configs) are provided, and [`~sample.h`](https://github.com/clockspot/arduino-clock/blob/master/arduino-clock/configs/%7Esample.h) includes all possible options with detailed comments.
+Various options, such as enabled functionality, RTC, display, I/O pins, timeouts, and control behaviors, are specified in a config file. This allows you to maintain configs for multiple clock hardware profiles, and simply include the relevant config at the top of `arduino-nixie.h` before compiling. Several [example configs](https://github.com/clockspot/arduino-clock/tree/master/arduino-clock/configs) are provided, and [`~sample.h`](https://github.com/clockspot/arduino-clock/blob/master/arduino-clock/configs/%7Esample.h) includes all possible options with detailed comments.
 
-You may also wish to adjust the defaults for the clock’s user-configurable values to best suit its intended use. Some of these are specified in the config; others are in the main code (`optsDef[]` for [settings](https://github.com/clockspot/arduino-clock/blob/master/INSTRUCTIONS.md#settings-menu) and `initEEPROM()` for other values).
+You may also wish to adjust the defaults for the clock’s user-configurable values to best suit its intended use, in case the user performs a hard reset. Some of these are specified in the config; others, for now, are hardcoded in `arduino-nixie.ino` (`optsDef[]` for [settings](https://github.com/clockspot/arduino-clock/blob/master/INSTRUCTIONS.md#settings-menu) and `initEEPROM()` for other values).
 
 I use the Arduino IDE to compile and upload, due to the use of various Arduino and Arduino-oriented libraries. Make sure the relevant libraries are installed in the Library Manager, per the config in use.
 
-* EEPROM (Arduino) for AVR Arduinos (e.g. original Nano)
+* EEPROM (Arduino) for AVR Arduinos (e.g. classic Nano)
 * SPI (Arduino) and [LedControl](http://wayoda.github.io/LedControl) for MAX7219-based displays
 * [Encoder](https://github.com/PaulStoffregen/Encoder) if rotary encoder is used for Up/Down inputs
 * Arduino_LSM6DS3 (Arduino) if using Nano 33 IoT’s IMU for inputs
@@ -57,4 +57,4 @@ I use the Arduino IDE to compile and upload, due to the use of various Arduino a
 Before compiling and uploading, you will need to select the correct board, port, and (for AVR) processor in the IDE’s Tools menu.
 
 * If your Arduino does not appear as a port option, you may have a clone that requires [drivers for the CH340 chipset](https://sparks.gogo.co.nz/ch340.html).
-* If upload fails for an ATMega328P Arduino (e.g. original Nano), try selecting/unselecting “Old Bootloader” in the processor menu.
+* If upload fails for an ATMega328P Arduino (e.g. classic Nano), try selecting/unselecting “Old Bootloader” in the processor menu.
diff --git a/TODO.md b/TODO.md
@@ -9,10 +9,11 @@
 	* wi-fi credential save fails if keys are part of the string?
 	* DST calc may behave unpredictably between 1–2am on fallback day
 	* Redo NTP on startup if it failed (networkStartWifi())
-	* Handle 2038+ epochs
+	* Make [2036-ready](https://en.wikipedia.org/wiki/Year_2038_problem#Network_Time_Protocol_timestamps)
 	* Notice when a leap second is coming and handle it
 	* When setting page is used to set day counter and date, and the month changes, set date max. For 2/29 it should just do 3/1 probably.
   * Weather support
+  * Stop using strings? There is plenty of RAM available on SAMD I think
 * Input: support other IMU orientations
 * When day counter is set to count up from 12/31, override to display 365/366 on that date
 * Bitmask to enable/disable features?
diff --git a/arduino-nixie/arduino-nixie.ino b/arduino-nixie/arduino-nixie.ino
@@ -749,7 +749,6 @@ bool initEEPROM(bool hard){
   if(hard || readEEPROM(6,false)<1 || readEEPROM(6,false)>31) changed += writeEEPROM(6,31,false,false); //6: ...31st. (This gives the day of the year)
   if(hard) changed += writeEEPROM(7,0,false,false); //7: Alt function preset
   //8: TODO functions/pages enabled (bitmask)
-  if(hard || readEEPROM(9,false)>1) changed += writeEEPROM(9,1,false,false); //9: NTP sync on
   if(hard) changed += writeEEPROM(15,0,false,false); //15: last known DST on flag - clear on hard reset (to match the reset RTC/auto DST/anti-poisoning settings to trigger midnight tubes as a tube test)
   if(networkSupported()){
     if(hard){ //everything in here needs no range testing
@@ -762,10 +761,11 @@ bool initEEPROM(bool hard){
       changed += writeEEPROM(54, 27,false,false);
       //Serial.print(readEEPROM(51,false),DEC); Serial.print(F(".")); Serial.print(readEEPROM(52,false),DEC); Serial.print(F(".")); Serial.print(readEEPROM(53,false),DEC); Serial.print(F(".")); Serial.println(readEEPROM(54,false),DEC);
       //55-86 Wi-Fi SSID (32 bytes)
-      //TODO
       //87-150 Wi-Fi WPA passphrase/key or WEP key (64 bytes)
-      //TODO
+      for(byte i=0; i<96; i++) changed += writeEEPROM(55+i,0,false,false); //Clear out the old values (32+64+1)
     }
+    //9 NTP sync enabled
+    if(hard || readEEPROM(9,false)>1) changed += writeEEPROM(9,0,false,false);
     //151 Wi-Fi WEP key index
     if(hard || readEEPROM(151,false)>3) changed += writeEEPROM(151,0,false,false);
   } //end network supported
@@ -930,7 +930,7 @@ void checkRTC(bool force){
     }
     
     //NTP cue at :59:00
-    if(rtcGetMinute()==59 && networkSupported() && readEEPROM(9,false)){
+    if(rtcGetMinute()==59 && networkSupported()){
       if(rtcGetSecond()==0) cueNTP();
       if(rtcGetSecond()==30 && ntpSyncAgo()>=30000) cueNTP(); //if at first you don't succeed...
     }
diff --git a/arduino-nixie/network.cpp b/arduino-nixie/network.cpp
@@ -16,8 +16,14 @@
 //Needs to be able to save to persistent storage
 #include "storage.h"
 
-String wssid = "Riley";
-String wpass = "5802301644"; //wpa pass or wep key
+//Volatile vars that back up the wifi creds in EEPROM
+// 55-86 Wi-Fi SSID (32 bytes)
+// 87-150 Wi-Fi WPA passphrase/key or WEP key (64 bytes)
+// 151 Wi-Fi WEP key index (1 byte)
+//If the EEPROM ssid/pass are a full 32/64 chars, there won't be room for the termination character '\0', we'll add that when reading
+//TODO consider making these char arrays - but the memory usage on SAMD isn't bad as-is
+String wssid = "";
+String wpass = ""; //wpa pass or wep key
 byte wki = 0; //wep key index - 0 if using wpa
 
 unsigned int localPort = 2390; // local port to listen for UDP packets
@@ -39,7 +45,15 @@ void initNetwork(){
   //Check status of wifi module up front
   //if(WiFi.status()==WL_NO_MODULE){ Serial.println(F("Communication with WiFi module failed!")); while(true); }
   //else if(WiFi.firmwareVersion()<WIFI_FIRMWARE_LATEST_VERSION) Serial.println(F("Please upgrade the firmware"));
-  networkStartWiFi();  
+  //Get wifi credentials out of EEPROM - see wssid/wpass definitions above
+  //Read until a termination character is reached
+  for(byte i=0; i<32; i++){ if(readEEPROM(55+i,false)=='\0') break; wssid.concat((char)(readEEPROM(55+i,false))); } //Read in the SSID
+  for(byte i=0; i<64; i++){ if(readEEPROM(87+i,false)=='\0') break; wpass.concat((char)(readEEPROM(87+i,false))); } //Read in the pass
+  wki = readEEPROM(151,false); //Read in the wki
+  Serial.print(F("wssid=")); Serial.println(wssid);
+  Serial.print(F("wpass=")); Serial.println(wpass);
+  Serial.print(F("wki=")); Serial.println(wki);
+  networkStartWiFi();
 }
 void cycleNetwork(){
   checkClients();
@@ -130,7 +144,7 @@ unsigned long ntpSyncAgo(){
 
 void cueNTP(){
   // We don't want to let other code startNTP() directly since it's normally asynchronous, and that other code may delay the time until we can check the result. Exception is forced call from admin page, which calls startNTP() synchronously.
-  ntpCued = true;
+  if(readEEPROM(9,false)) ntpCued = true;
 }
 
 int startNTP(bool synchronous){ //Called at intervals to check for ntp time
@@ -422,7 +436,7 @@ void checkClients(){
           
         client.print(F("<li id='ntpserverli' style='display: ")); if(readEEPROM(9,false)==0) client.print(F("none")); else client.print(F("block")); client.print(F(";'><label>NTP server</label><input type='text' id='ntpip' onchange='promptsave(\"ntpip\")' onkeyup='promptsave(\"ntpip\")' onblur='unpromptsave(\"ntpip\"); save(this)' value='")); client.print(readEEPROM(51,false),DEC); client.print(F(".")); client.print(readEEPROM(52,false),DEC); client.print(F(".")); client.print(readEEPROM(53,false),DEC); client.print(F(".")); client.print(readEEPROM(54,false),DEC); client.print(F("' />")); client.print(F(" <a id='ntpipsave' href='#' onclick='return false' style='display: none;'>save</a><br/><span class='explain'><a href='https://en.wikipedia.org/wiki/IPv4#Addressing' target='_blank'>IPv4</a> address, e.g. one of <a href='https://tf.nist.gov/tf-cgi/servers.cgi' target='_blank'>NIST's time servers</a></span></li>"));
         
-        client.print(F("<li><label>Current time</label><input type='number' id='todh' onchange='promptsave(\"tod\")' onkeyup='promptsave(\"tod\")' onblur='unpromptsave(\"tod\"); savetod(\"tod\")' min='0' max='23' step='1' value='")); client.print(rtcGetHour(),DEC); client.print(F("' />&nbsp;:&nbsp;<input type='number' id='todm' onchange='promptsave(\"tod\")' onkeyup='promptsave(\"tod\")' onblur='unpromptsave(\"tod\"); savetod(\"tod\")' min='0' max='59' step='1' value='")); client.print(rtcGetMinute(),DEC); client.print(F("' /><input type='hidden' id='tod' /> <a id='todsave' href='#' onclick='return false' style='display: none;'>save</a><br/><span class='explain'>24-hour format. Seconds will reset to 0 when saved.</span></li>"));
+        client.print(F("<li><label>Current time</label><input type='number' id='curtodh' onchange='promptsave(\"curtod\")' onkeyup='promptsave(\"curtod\")' onblur='unpromptsave(\"curtod\"); savetod(\"curtod\")' min='0' max='23' step='1' value='")); client.print(rtcGetHour(),DEC); client.print(F("' />&nbsp;:&nbsp;<input type='number' id='curtodm' onchange='promptsave(\"curtod\")' onkeyup='promptsave(\"curtod\")' onblur='unpromptsave(\"curtod\"); savetod(\"curtod\")' min='0' max='59' step='1' value='")); client.print(rtcGetMinute(),DEC); client.print(F("' /><input type='hidden' id='curtod' /> <a id='curtodsave' href='#' onclick='return false' style='display: none;'>save</a><br/><span class='explain'>24-hour format. Seconds will reset to 0 when saved.</span></li>"));
         
         client.print(F("<li><label>Time format</label><select id='b16' onchange='save(this)'>")); for(char i=1; i<=2; i++){ client.print(F("<option value='")); client.print(i,DEC); client.print(F("'")); if(readEEPROM(16,false)==i) client.print(F(" selected")); client.print(F(">")); switch(i){
           case 1: client.print(F("12-hour")); break;
@@ -760,7 +774,7 @@ void checkClients(){
         //client.print(F(""));
       } //end get
       else { //requestType==2 - handle what was POSTed
-        String clientReturn = "ok"; //To return an error, set it here. An empty response generates "Error".
+        bool clientReturn = false; //Mark true when sending an error. If none, "ok" is sent at end. If nothing sent (crash), client displays generic error.
         //client.print(currentLine);
         //syncfreq=hr
         //syncfreq=min
@@ -775,13 +789,12 @@ void checkClients(){
           wpass = currentLine.substring(startPos,endPos);
           startPos = endPos+5;
           wki = currentLine.substring(startPos).toInt();
-            // client.print(F(" wssid="));
-            // client.print(wssid);
-            // client.print(F(" wpass="));
-            // client.print(wpass);
-            // client.print(F(" wki="));
-            // client.print(wki);
-            // client.println();
+          //Persistent storage - see wssid/wpass definitions above
+          for(byte i=0; i<97; i++) writeEEPROM(55+i,0,false,false); //Clear out the old values (32+64+1)
+          for(byte i=0; i<wssid.length(); i++) writeEEPROM(55+i,wssid[i],false,false); //Write in the SSID
+          for(byte i=0; i<wpass.length(); i++) writeEEPROM(87+i,wpass[i],false,false); //Write in the pass
+          writeEEPROM(151,wki,false,false); //Write in the wki
+          commitEEPROM(); //commit all the above
           requestType = 3; //triggers an admin restart after the client is closed, below
         } else if(currentLine.startsWith(F("ntpip"))){
           //e.g. ntpip=192.168.1.255
@@ -792,22 +805,24 @@ void checkClients(){
             ntpip[i] = octet; startPos = endPos+1;
             if(ntpip[i]!=octet){ parseOK = false; break; }
           }
-          if(!parseOK) clientReturn = "Error: invalid format";
+          if(!parseOK) { clientReturn = true; client.print(F("Error: invalid format")); }
           else for(byte i=0; i<4; i++) writeEEPROM(51+i,ntpip[i],false);
           //Serial.print(F("IP should be ")); Serial.print(ntpip[0],DEC); Serial.print(F(".")); Serial.print(ntpip[1],DEC); Serial.print(F(".")); Serial.print(ntpip[2],DEC); Serial.print(F(".")); Serial.println(ntpip[3],DEC);
           //Serial.print(F("IP saved as ")); Serial.print(readEEPROM(51,false),DEC); Serial.print(F(".")); Serial.print(readEEPROM(52,false),DEC); Serial.print(F(".")); Serial.print(readEEPROM(53,false),DEC); Serial.print(F(".")); Serial.println(readEEPROM(54,false),DEC);
         } else if(currentLine.startsWith(F("syncnow"))){
+          //TODO this doesn't seem to return properly if the wifi was changed after the clock was booted - it syncs, but just hangs
           int ntpCode = startNTP(true);
           switch(ntpCode){
-            case -1: clientReturn = "Error: no Wi-Fi credentials."; break;
-            case -2: clientReturn = "Error: not connected to Wi-Fi."; break;
-            case -3: clientReturn = "Error: NTP response pending. Please try again shortly."; break; //should never see this one on the web since it's synchronous and the client blocks
-            case -4: clientReturn = "Error: too many sync requests in the last "; clientReturn += (NTP_MINFREQ/1000); clientReturn += " seconds. Please try again shortly."; break;
-            case -5: clientReturn = "Error: no NTP response received. Please confirm server."; break;
-            case 0: clientReturn = "synced"; break;
-            default: clientReturn = "Error: unhandled NTP code"; break;
+            case -1: client.print(F("Error: no Wi-Fi credentials.")); break;
+            case -2: client.print(F("Error: not connected to Wi-Fi.")); break;
+            case -3: client.print(F("Error: NTP response pending. Please try again shortly.")); break; //should never see this one on the web since it's synchronous and the client blocks
+            case -4: client.print(F("Error: too many sync requests in the last ")); client.print(NTP_MINFREQ/1000,DEC); client.print(F(" seconds. Please try again shortly.")); break;
+            case -5: client.print(F("Error: no NTP response received. Please confirm server.")); break;
+            case 0: client.print(F("synced")); break;
+            default: client.print(F("Error: unhandled NTP code")); break;
           }
-        } else if(currentLine.startsWith(F("tod"))){
+          clientReturn = true;
+        } else if(currentLine.startsWith(F("curtod"))){
           int tod = currentLine.substring(7).toInt();
           rtcSetTime(tod/60,tod%60,0);
           ntpSyncLast = 0;
@@ -876,7 +891,7 @@ void checkClients(){
           }
         }
         updateDisplay();
-        client.print(clientReturn);
+        if(!clientReturn) client.print(F("ok"));
       } //end post
     } //end if requestType
     
diff --git a/arduino-nixie/storage.cpp b/arduino-nixie/storage.cpp
@@ -13,6 +13,7 @@
 
 #define STORAGE_SPACE 152 //number of bytes
 byte storageBytes[STORAGE_SPACE]; //the volatile array of bytes
+#define WRITE_TO_EEPROM 1 //1 for production
 
 void initStorage(){
   //If this is SAMD, write starting values if unused
@@ -22,8 +23,10 @@ void initStorage(){
   Serial.print(F("16=")); Serial.println(EEPROM.read(16));
   if(!EEPROM.isValid() || EEPROM.read(16)==0 || EEPROM.read(16)==255){ //invalid eeprom, wipe it out
     for(byte i=0; i<STORAGE_SPACE; i++) EEPROM.update(i,0);
-    EEPROM.commit();
-    Serial.println(F("WARNING: FLASH EEPROM COMMIT per init"));
+    if(WRITE_TO_EEPROM){
+      EEPROM.commit();
+      Serial.println(F("WARNING: FLASH EEPROM COMMIT per init"));
+    }
   }
   #endif
   //Read from real persistent storage into storageBytes
@@ -56,7 +59,7 @@ bool writeEEPROM(int loc, int val, bool isInt, bool commit){
     EEPROM.update(loc,val);
   }
   #ifdef FLASH_AS_EEPROM
-    if(commit){
+    if(commit && WRITE_TO_EEPROM){
       EEPROM.commit(); //bad!! See TODO in storage.h
       Serial.println(F("WARNING: FLASH EEPROM COMMIT per write"));
     }
@@ -65,7 +68,9 @@ bool writeEEPROM(int loc, int val, bool isInt, bool commit){
 }
 void commitEEPROM(){
   #ifdef FLASH_AS_EEPROM
+  if(WRITE_TO_EEPROM){
     EEPROM.commit(); //bad!! See TODO in storage.h
     Serial.println(F("WARNING: FLASH EEPROM COMMIT by request"));
+  }
   #endif
 }
