Can bus battery monitor with OLED - Revision history

Legg: /* Notes */

2020-11-01T07:36:52Z

Notes

Legg: /* Notes */

2020-11-01T07:13:10Z

Notes

Legg: /* Code */

2020-11-01T07:03:26Z

Code

Legg: /* Code */

2020-11-01T07:00:46Z

Code

Legg: /* Code */

2020-11-01T07:00:23Z

Code

Legg at 19:04, 31 October 2020

2020-10-31T19:04:56Z

Legg: Created page with " //Arduino UNO //MCP2515 ////Pin 13 SPI clock ////Pin 12 MISO ////Pin 11 MOSI ////Pin 10 Cable Select //SSD1306 ////Pin A4 SDA ////Pin..."

2020-10-31T18:57:19Z

Created page with "<syntaxhighlight lang="C++" line='line'> //Arduino UNO //MCP2515 ////Pin 13 SPI clock ////Pin 12 MISO ////Pin 11 MOSI ////Pin 10 Cable Select //SSD1306 ////Pin A4 SDA ////Pin..."

New page

<syntaxhighlight lang="C++" line='line'>
//Arduino UNO
//MCP2515
////Pin 13 SPI clock
////Pin 12 MISO
////Pin 11 MOSI
////Pin 10 Cable Select
//SSD1306
////Pin A4 SDA
////Pin A5 SCL
//ALARM
////Pin 08 Enable

#include <SPI.h>
#include "mcp_can.h"

//Graphics
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
#define OLED_RESET 4 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

//Software constants
#define NUMPACKS 5 //Number of packs installed on line. Must edit knownID[] array
#define NUMCELLS 8 //Hazardous to modify
#define REFRESH 1000 //Refresh rate display
#define ALARM 3.645 //Alarm threshold

bool buzzer = HIGH;
const int spiCSPin = 10;
boolean ledON = 1;
float voltage[NUMPACKS][NUMCELLS];
float sum[NUMPACKS];
long knownID[NUMPACKS] = {0x00000004, 0x00000006, 0x00000020, 0x00000021, 0x00000022};
long packID;
int slot;

float Pack = 0.0;

unsigned char bufA[10];
unsigned char buf0[10];
unsigned char buf3[10];
unsigned char buf5[10];
unsigned char buf20[10];
unsigned char buf21[10];
unsigned char buf22[10];

unsigned long time;
unsigned long TriggerTime = 0;
unsigned long unknownId = 0;

MCP_CAN CAN(spiCSPin);

void setup()
{
Serial.begin(115200);

//Graphics
Serial.println(F("Starting"));
/*
if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) //Line 66
{ // Address 0x3D for 128x64
Serial.println(F("SSD1306 allocation failed"));
for(;;); // Don't proceed, loop forever
}
Serial.println(F("Hello"));

//If you comment line 74, then line 66 will fail
testdrawchar(); //Line 74
*/
//Pin 8 voltage alarm
pinMode(8, OUTPUT);
//Initialize against undefined values
for(int i=0;i<NUMPACKS;i++)
{
for(int j=0;j<NUMCELLS;j++)
{
voltage[i][j]=0.0;
}
}

while (CAN_OK != CAN.begin(CAN_125KBPS,MCP_8MHz))
{
Serial.println("CAN BUS Init Failed, waiting for hardware...");
delay(100);
}
Serial.println("CAN BUS Init OK!");
}

void loop()
{
long msgID = 0x00000FFF;
bool skip = LOW;
unsigned char len = 0;
unsigned char buf[10];
unsigned long canId = 0x00000000;
if(CAN_MSGAVAIL == CAN.checkReceive())
{
CAN.readMsgBuf(&len, buf);
canId = CAN.getCanId();
if (canId & 0xFFFFF000 != 0x08010000)
{
Serial.println("Unsupported device attached! Correct and restart monitor.");
Serial.print("Device: 0x");
Serial.print(canId & 0xFFFFF000,HEX);
Serial.println(".");
//Sound alarm
digitalWrite(8,1);
while(1){}
}
//detect if pack is registered
packID = canId & 0x000000FF;
slot = 0xFF;
for(int i = 0; i<NUMPACKS ; i++)
{
if(knownID[i]==packID)
{
slot=i;
}
if(i==NUMPACKS-1 && slot==0xFF)
{
Serial.println("Unregistered Device attached! Skipping!");
Serial.print(" Device : 0x");
Serial.print(packID,HEX);
Serial.println(".");
skip = HIGH;
}
}
//If pack is registered, collect it's data into local storage.
if(!skip)
{
msgID = canId & 0x00000F00;
//Interpret message 3
if (msgID == 0x00000300)
{
for(int i = 0; i<len; i++)
{
buf3[i] = buf[i];
}
}
//Interpret message 3
else if (msgID == 0x00000500)
{
for(int i = 0; i<len; i++)
{
buf5[i] = buf[i];
}
}
//Interpret message A
else if (msgID == 0x00000A00)
{
for(int i = 0; i<len; i++)
{
bufA[i] = buf[i];
}
}
//Interpret message 0
else if (msgID == 0x00000000)
{
for(int i = 0; i<len; i++)
{
buf0[i] = buf[i];
}
}
//Interpret message 2
else if (msgID == 0x00000200)
{
if (buf[0] == 0)
{
unsigned int Cell = buf[2] * 256 + buf[1];
voltage[slot][7] = Cell / 1000.0;
Cell = buf[4] * 256 + buf[3];
voltage[slot][6] = Cell / 1000.0;
Cell = buf[6] * 256 + buf[5];
voltage[slot][5] = Cell / 1000.0;

for(int i = 0; i<len; i++)
{
buf20[i] = buf[i];
}
}
if (buf[0] == 1)
{
unsigned int Cell = buf[2] * 256 + buf[1];
voltage[slot][4] = Cell / 1000.0;
Cell = buf[4] * 256 + buf[3];
voltage[slot][3] = Cell / 1000.0;
Cell = buf[6] * 256 + buf[5];
voltage[slot][2] = Cell / 1000.0;

for(int i = 0; i<len; i++)
{
buf21[i] = buf[i];
}
}
if (buf[0] == 2)
{
unsigned int Cell = buf[2] * 256 + buf[1];
voltage[slot][1] = Cell / 1000.0;
Cell = buf[4] * 256 + buf[3];
voltage[slot][0] = Cell / 1000.0;

for(int i = 0; i<len; i++)
{
buf22[i] = buf[i];
}
}
}
else
{
unknownId = canId;
Serial.println("Unexpected Message type detected!");
Serial.println(canId & 0x00000F00, HEX);
}
//Run every REFRESHms
time = millis();
if (time >= TriggerTime)
{
//Detect for alarm condition
for(int i=0; i<NUMPACKS;i++)
{
for(int j=0;j<NUMCELLS;j++)
{
if(voltage[i][j]>=ALARM)
buzzer=HIGH;
else
buzzer=LOW;
}
}
//Execute alarm condition
if(buzzer)
digitalWrite(8,1);
else
digitalWrite(8,0);

TriggerTime = TriggerTime + REFRESH;
Pack=0.0;
//Dump cell voltages to CSV
for(int i=0; i<NUMPACKS;i++)
{
Pack=0.0;
for(int j=0; j<NUMCELLS ; j++)
{
Serial.print(voltage[i][j],3);
Serial.print(",");
Pack += voltage[i][j];
}
Serial.print(Pack,3);
if(NUMPACKS-1!=i)
Serial.print(',');
else
Serial.println(Pack,3);
}

if(unknownId != 0)
{
Serial.print("Unknown Message: ");
Serial.print(unknownId, HEX);
Serial.println();
}
}
}
else skip=LOW;
}
}

void testdrawchar(void)
{
display.clearDisplay();
display.setTextSize(1); // Normal 1:1 pixel scale
display.setTextColor(SSD1306_WHITE); // Draw white text
display.setCursor(0, 0); // Start at top-left corner
display.cp437(true); // Use full 256 char 'Code Page 437' font

//If you comment this while(1), initialization at line 66 will fail
while(1)
{
Serial.println("Testing...");
display.setCursor(0,0); // Start at top-left corner
display.println(F(" * Testing * "));
display.display();
display.clearDisplay();
delay(500);
}
}

</syntaxhighlight>

← Older revision		Revision as of 07:36, 1 November 2020
Line 9:		Line 9:

	If EN_SCREEN is defined, and EN_ARRAY is defined : An initialization error exists with the display.begin() function in in the setup() section, even though the added lines that are in the loop() section and not yet executed. The existence of these array functions in the code segment cause the display.begin() to fail.		If EN_SCREEN is defined, and EN_ARRAY is defined : An initialization error exists with the display.begin() function in in the setup() section, even though the added lines that are in the loop() section and not yet executed. The existence of these array functions in the code segment cause the display.begin() to fail.
		+
		+	The EN_SCREEN code is within lines 68-75.
		+
		+	The EN_ARRAY code is within lines 240-243, 263, 265 and 267.

	==Code==		==Code==

@@ Line 2: / Line 2: @@
 This code is designed for the Arduino UNO.  Attached is a SSD1306 compatible OLED module and a MCP2515 CAN module.  This is designed to monitor cell voltages in large battery packs containing LiFePO4 cells in arrays.  In this particular instance, there are 5 packs, each containing 8 cells.  The output is delivered on 1 second intervals into a spreadsheet friendly format.
 ==Notes==
-The OLED screen is disabled due to unexplained interactions with the Arduino IDE as explained in comments on lines 73-74 and 282.
+There is unexplained behavior in this sketch.  Two DEFINE clauses were created EN_SCREEN (enable screen) and EN_ARRAY (enable array).
 ==Code==
 <syntaxhighlight lang="C++" line='line'>

@@ Line 6: / Line 6: @@
 <syntaxhighlight lang="C++" line='line'>
 //#define EN_SCREEN
-#define EN_ARRAY
+//#define EN_ARRAY
 //Arduino UNO

← Older revision		Revision as of 19:04, 31 October 2020
Line 1:		Line 1:
		+	==Synopsis==
		+	This code is designed for the Arduino UNO. Attached is a SSD1306 compatible OLED module and a MCP2515 CAN module. This is designed to monitor cell voltages in large battery packs containing LiFePO4 cells in arrays. In this particular instance, there are 5 packs, each containing 8 cells. The output is delivered on 1 second intervals into a spreadsheet friendly format.
		+	==Notes==
		+	The OLED screen is disabled due to unexplained interactions with the Arduino IDE as explained in comments on lines 73-74 and 282.
		+	==Code==
	<syntaxhighlight lang="C++" line='line'>		<syntaxhighlight lang="C++" line='line'>
	//Arduino UNO		//Arduino UNO

@@ Line 73: / Line 73: @@
 #ifdef EN_SCREEN
-   if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) //Line 66
+   if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C))
    { // Address 0x3D for 128x64
      Serial.println(F("SSD1306 allocation failed"));
      for(;;); // Don't proceed, loop forever
+   }
    testdrawchar();
 #endif

@@ Line 5: / Line 5: @@
 ==Code==
 <syntaxhighlight lang="C++" line='line'>
 //Arduino UNO
 //MCP2515
@@ Line 68: / Line 71: @@
    //Graphics
-  Serial.println(F("Starting"));
-/*
+#ifdef EN_SCREEN
    if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) //Line 66
    { // Address 0x3D for 128x64
      Serial.println(F("SSD1306 allocation failed"));
      for(;;); // Don't proceed, loop forever
-−
+   }
    //If you comment line 74, then line 66 will fail
    testdrawchar();  //Line 74
-*/
+#endif
    //Pin 8 voltage alarm
    pinMode(8, OUTPUT);
@@ Line 99: / Line 102: @@
+   }
    Serial.println("CAN BUS  Init OK!");
+}
 void loop()
+{
    long msgID = 0x00000FFF;
    bool skip = LOW;
@@ Line 108: / Line 113: @@
    unsigned char buf[10];
    unsigned long canId = 0x00000000;
    if(CAN_MSGAVAIL == CAN.checkReceive())
+   {
      CAN.readMsgBuf(&len, buf);
      canId = CAN.getCanId();
@@ Line 143: / Line 150: @@
      if(!skip)
+     {
        msgID = canId & 0x00000F00;
        //Interpret message 3
@@ Line 226: / Line 234: @@
          Serial.println(canId & 0x00000F00, HEX);
+       }
        //Run every REFRESHms
        time = millis();
        if (time >= TriggerTime)
+       {
          //Detect for alarm condition
          for(int i=0; i<NUMPACKS;i++)
@@ Line 235: / Line 245: @@
            for(int j=0;j<NUMCELLS;j++)
+           {
-             if(voltage[i][j]>=ALARM)
+#ifdef EN_ARRAY
                buzzer=HIGH;
              else
                buzzer=LOW;
+           }
+         }
          //Execute alarm condition
          if(buzzer)
            digitalWrite(8,1);
          else
            digitalWrite(8,0);
          TriggerTime = TriggerTime + REFRESH;
          Pack=0.0;
          //Dump cell voltages to CSV
          for(int i=0; i<NUMPACKS;i++)
+         {
            Pack=0.0;
            for(int j=0; j<NUMCELLS ; j++)
+           {
-             Serial.print(voltage[i][j],3);
+#ifdef EN_ARRAY
              Serial.print(",");
-             Pack += voltage[i][j];
+#ifdef EN_ARRAY
+           }
            Serial.print(Pack,3);
@@ Line 263: / Line 280: @@
              Serial.print(',');
            else
-             Serial.println(Pack,3);
+             Serial.println();
+         }
@@ Line 272: / Line 289: @@
            Serial.println();
+         }
+       }
+     }
      else skip=LOW;
+   }
+}
@@ Line 285: / Line 305: @@
    display.setCursor(0, 0);     // Start at top-left corner
    display.cp437(true);         // Use full 256 char 'Code Page 437' font
    Serial.println("Testing...");
-  //If you comment this while(1), initialization at line 66 will fail
+  display.setCursor(0,0);             // Start at top-left corner
-   while(1)
+  display.println(F("    * Testing *"));
+  display.display();
-    Serial.println("Testing...");
+  display.clearDisplay();
-    display.setCursor(0,0);             // Start at top-left corner
+  delay(500);
-    display.println(F("    * Testing *  "));
+   display.setCursor(28,25);             // Start at top-left corner
-    display.display();
+  display.println(F("    * Testing *"));
-    display.clearDisplay();
+  display.display();
-    delay(500);
+  delay(500);
+  display.clearDisplay();
+}
 </syntaxhighlight>