Revision 1:7749656733dd, committed 2020-08-24

Comitter:

kuutei

Date:

Mon Aug 24 05:29:53 2020 +0000

Parent:

0:56122e281547

Child:

2:18d8f9d3286c

Commit message:

sort of working

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DS1820.lib	Mon Aug 24 05:29:53 2020 +0000
@@ -0,0 +1,1 @@
+https://os.mbed.com/users/hudakz/code/DS1820/#74a4ff420541

--- a/main.cpp	Mon Aug 24 04:09:04 2020 +0000
+++ b/main.cpp	Mon Aug 24 05:29:53 2020 +0000
@@ -6,11 +6,14 @@
 #include <sstream>
 
 #include "SSD1306I2C.h"
+#include "DS1820.h"
 
 #define OLED_ADR 0x3C
 #define OLED_SDA I2C_SDA
 #define OLED_SCL I2C_SCL
 
+#define DS18B20_DATA PB_4
+
 
 // Blinking rate in milliseconds
 #define BLINKING_RATE_MS                                                    5000
@@ -20,6 +23,10 @@
 
 Serial pc(USBTX,USBRX);
 
+SSD1306I2C oled_i2c(OLED_ADR, OLED_SDA, OLED_SCL);
+
+DS1820 ds1820_sensor(DS18B20_DATA);
+
 //DigitalIn mybutton(USER_BUTTON);
 AnalogIn   divider_analogin(A0);
 AnalogIn    vref(ADC_VREF);
@@ -27,21 +34,23 @@
 //AnalogIn adc_refint(VREF_INT);
 
 DigitalInOut toggleOut(PA_14, PIN_OUTPUT, OpenDrainNoPull, 0);
-bool enableChargingState = false; //reflects internal state of TP4056 control thread
+bool TP4056ChargingState = false; //reflects internal state of TP4056 control thread
 
 InterruptIn chargeButton(USER_BUTTON);
-bool buttonPressed = false; //set to true by button ISR, set to false when acknowledged
+volatile bool buttonPressed = false; //set to true by button ISR, set to false when acknowledged
 
-SSD1306I2C oled_i2c(OLED_ADR, OLED_SDA, OLED_SCL);
+bool batteryPresenceState = false;
 
 float bat_voltage = -1.11;
 float bat_voltage_avg = -1.11;
 float vddref_voltage = -1.11;
 
+float ds18b20_temperature = -301.0;
 
 //Configurable protection conditions
 float MAX_VOLTAGE = 4.25; //default: no more than 4.25v
 float MIN_VOLTAGE = 2.5; //default: no less than 2.5v
+float MIN_DETECT_VOLTAGE = 0.5; //default: no less than 0.3v
 float MAX_TEMPERATURE = 40.0; //default: no more than 40C
 float MIN_TEMPERATURE = 10.0; //default: no less than 10C
 uint64_t MAX_TIME_ms = 3600000; //default: no more than 1h
@@ -54,29 +63,26 @@
     
     while (true) {
         led = !led;
-        //thread_sleep_for(BLINKING_RATE_MS);
         ThisThread::sleep_for(BLINKING_RATE_MS);
     }
 }
 
-//TODO: make this an ISR that causes an immediate read of the analog pin
-void pa14_toggle()
-{
-
-}
 
 // Button to initiate / stop charging
 // Called on button rise
 // Set to true to signal to EN control thread that button was pressed
-void buttonISR
+void buttonISR()
 {
+    static uint64_t lastButtonPushTime = 0;
+    
     uint64_t now = Kernel::get_ms_count();
-    uint64_t lastButtonPushTime = now;
+    
     const uint64_t buttonMinimumWaitTime = 500; //minimum 500 ms wait between button pushes
     
     if(Kernel::get_ms_count() - lastButtonPushTime > buttonMinimumWaitTime)
     {
         buttonPressed = true;
+        lastButtonPushTime = now;
     }
        
 }
@@ -135,9 +141,31 @@
 // Reads DS18B20 sense temperature
 void TemperatureInputThread()
 {
+    int ds18b20_result = 0;
+    float temp;
+    
     while(true)
     {
+        ds1820_sensor.startConversion();   // start temperature conversion from analog to digital
+        // let DS1820 complete the temperature conversion
+        ThisThread::sleep_for(1.0);
+        ds18b20_result = ds1820_sensor.read(temp); // read temperature from DS1820 and perform cyclic redundancy check (CRC)
         
+        switch (ds18b20_result) {
+            case 0:                 // no errors -> 'temp' contains the value of measured temperature
+                //pc.printf("temp = %3.4f%cC\r\n", temp, 176);
+                ds18b20_temperature = temp;
+                break;
+
+            case 1:                 // no sensor present -> 'temp' is not updated
+                //pc.printf("no sensor present\n\r");
+                ds18b20_temperature = -302.0;
+                break;
+
+            case 2:                 // CRC error -> 'temp' is not updated
+                //pc.printf("CRC error\r\n");
+                ds18b20_temperature = -303.0;
+            }
         
         ThisThread::sleep_for(250);
 
@@ -147,10 +175,14 @@
 // Detect battery presence by voltage activity
 bool batteryPresent()
 {
-    if(bat_voltage_avg > 0.0 && bat_voltage_avg)
+    if(bat_voltage_avg > MIN_DETECT_VOLTAGE)
     {
         return true;   
     }
+    else
+    {
+        return false;   
+    }
 }
 
 void TP4056ControlThread()
@@ -164,13 +196,35 @@
        while(true)
        {
             //First check conditions to see if charging should be enabled or disabled
+            bool temperature_en = ( ( ds18b20_temperature < MAX_TEMPERATURE ) && ( ds18b20_temperature > MIN_TEMPERATURE ) );
+            bool voltage_en = ( ( bat_voltage_avg  < MAX_VOLTAGE ) && ( bat_voltage_avg > MIN_VOLTAGE ) );
+            bool presence_en = batteryPresent();
+            bool charge_time_exceeded = ( (Kernel::get_ms_count() - chargeStartTime ) > MAX_TIME_ms);
+            
             //Charging can be enabled if battery is present, no protections triggered, and user starts the charge
             if(enableCharging == false)
+            {                
+                if( voltage_en && temperature_en && presence_en && buttonPressed )
+                {
+                    enableCharging = true;
+                    buttonPressed = false;
+                }
+            }
+            //Charging must be stopped if overvoltage, overtemperature, overtime, battery removed, or user pushes button
+            else
             {
-                bool temperature_en = (MAX_TEMPERATURE);
+                //Disable charging if any protection condition is triggered
+                if( !voltage_en || !temperature_en || !presence_en )
+                {
+                    enableCharging = false;
+                }
+                //or if user pushed button
+                else if(buttonPressed)
+                {    
+                    buttonPressed = false;   
+                }
             }
             
-            //Charging must be stopped if overvoltage, overtemperature, overtime, battery removed, or user pushes button
             
             //With charge state calculated, realize it on the CE pin
             //Allow pullup to 5V to enable charging at CE pin
@@ -186,7 +240,7 @@
             } 
             
             //Update flag that indicates state of TP4056 CE pin to other threads
-            enableChargingState = enableCharging;
+            TP4056ChargingState = enableCharging;
         
            ThisThread::sleep_for(100);
        }
@@ -204,7 +258,7 @@
         std::string voltage_output = "Voltage: " + stream.str();
         oled_i2c.drawString(0, 0, voltage_output.c_str() );
         
-        if(enableChargingState){
+        if(TP4056ChargingState){
             oled_i2c.drawString(0, 16, "CE: Enabled");
         } else {
             oled_i2c.drawString(0, 16, "CE: Disabled");  
@@ -296,7 +350,7 @@
         pc.printf("ADC0 1s max: %6.4f\r\n", bat_voltage_max);
         pc.printf("ADC0 1s avg: %6.4f\r\n", bat_voltage_avg);
         pc.printf("VDDREF Reading: %6.4f\r\n", vddref_voltage);
-        pc.printf("ADC0 time (nominal 1000ms): %d\r\n", (now-lastADCStartTime));
+        pc.printf("ADC0 time (nominal 1000ms): %llu\r\n", (now-lastADCStartTime));
         
     }