So I’m trying to set an arduino nano to do screen on/off and brightness control but to also have the RealDash CAN control with it as I’m planning on using the arduino for several inputs and such, and to let most of the actions and triggers to be controlled through RealDash instead of the arduino code. Ultimate plan is to have the dash rheostat connected to the arduino as a potentiometer input, have a light sensor as an input (this might eventually go over canbus, but for now I’m breadboarding it), and have a digital input for the parking lights.
The LCD backlight is enabled by a 5v input on the ENA line and brightness is controlled via the DIM line and based on the amount of voltage on the line, it will dim the panel. Using PWM also works on the DIM input. I’ve gotten it to dim and work properly when not using the CANBUS to RealDash. From what I can tell, I can’t set PWM signals in RealDash, so what I’m trying to do is when digital 5 is turned on, instead of being a straight on/off signal, I want it to be a PWM signal controlled by the dash knob, and if digital 5 is turned off in RealDash, that it goes to off. I’m using the arduino example code from RealDash right now and attached is the sketch.
Can someone help with what I’m doing wrong in the sketch?
/**
* ============================================================================
* Name : RealDash_CAN_2way.ino
* Part of : RealDash
* Author : Jani Immonen
* Created : 15.10.2017
*
* Arduino example sketch of how to use RealDash CAN protocol.
* This example code is free for any use.
*
* www.realdash.net
* ============================================================================
**/
// Arduino digital and analog pins
// digital pin statuses are stored as bits in one variable
unsigned int digitalPins = 0;
// analog pin values are stored in array of ints
int analogPins[7] = {0};
unsigned int rpm = 0;
unsigned int kpa = 992; // 99.2
unsigned int tps = 965; // 96.5
unsigned int clt = 80; // 80 - 100
unsigned int textCounter = 0;
// incoming data
byte incomingFrame[17] = { 0 };
unsigned int incomingFramePos = 0;
// if READWRITE_PINS is defined, the values are read from and written to Arduino
// digital and analog pins.
#define READWRITE_PINS
void setup()
{
#if defined (READWRITE_PINS)
// set digital pins as outputs
for (int i=1; i<14; i++)
{
pinMode(i, OUTPUT);
}
#endif
// init serial
Serial.begin(115200);
delay(100);
}
void loop()
{
ReadDigitalStatuses();
ReadAnalogStatuses();
SendCANFramesToSerial();
ReadIncomingSerialData();
/*
// just some dummy values for simulated engine parameters
if (rpm++ > 10000)
{
rpm = 500;
}
if (kpa++ > 2500)
{
kpa = 10;
}
if (tps++ > 1000)
{
tps = 0;
}
if (clt++ > 230)
{
// all values in frame are handled as unsigned values. To use negative values,
// offset actual value and write corresponding conversion to XML file imported to RealDash
// From RealDash 1.7.6 its also possible to specify value as signed="true" in XML file.
clt = 0;
}
*/
// simple counter for sending the text frame to avoid sending it too often.
if (textCounter++ > 4000)
{
textCounter = 0;
}
//DigitalTest();
//AnalogTest();
delay(5);
}
void DigitalTest()
{
for (int i=1; i<14; i++)
{
Serial.print("Digital Output ");
Serial.println(i);
Serial.println(digitalRead(i));
delay(1000);
}
}
void ReadDigitalStatuses()
{
#if defined (READWRITE_PINS)
// read status of digital pins (1-13)
digitalPins = 0;
int bitposition = 0;
for (int i=1; i<14; i++)
{
if (digitalRead(i) == HIGH) digitalPins |= (1 << bitposition);
bitposition++;
//Serial.print("Digital Output ");
//Serial.println(i);
//Serial.println(digitalRead(i));
//Serial.print("Bitposition ");
//Serial.println(bitposition);
//Serial.println("Digital Pins Value ");
//Serial.println(digitalPins);
//delay(1000);
}
#endif
}
void AnalogTest()
{
for (int i=0; i<7; i++)
{
Serial.print("Analog Output ");
Serial.println(i);
Serial.println(analogRead(i));
delay(1000);
}
}
void ReadAnalogStatuses()
{
#if defined (READWRITE_PINS)
// read analog pins (0-7)
for (int i=0; i<7; i++)
{
analogPins[i] = analogRead(i);
}
#endif
}
void SendCANFramesToSerial()
{
byte frameData[8];
// build & send CAN frames to RealDash.
// a CAN frame payload is always 8 bytes containing data in a manner
// described by the RealDash custom channel description XML file
// all multibyte values are handled as little endian by default.
// endianess of the values can be specified in XML file if it is required to use big endian values
// build 1st CAN frame, RPM, MAP, CLT, TPS (just example data)
memcpy(frameData, &rpm, 2);
memcpy(frameData + 2, &kpa, 2);
memcpy(frameData + 4, &clt, 2);
memcpy(frameData + 6, &tps, 2);
// write first CAN frame to serial
SendCANFrameToSerial(3200, frameData);
// build 2nd CAN frame, Arduino digital pins and 2 analog values
memcpy(frameData, &digitalPins, 2);
memcpy(frameData + 2, &analogPins[0], 2);
memcpy(frameData + 4, &analogPins[1], 2);
memcpy(frameData + 6, &analogPins[2], 2);
// write 2nd CAN frame to serial
SendCANFrameToSerial(3201, frameData);
// build 3rd CAN frame, rest of Arduino analog values
memcpy(frameData, &analogPins[3], 2);
memcpy(frameData + 2, &analogPins[4], 2);
memcpy(frameData + 4, &analogPins[5], 2);
memcpy(frameData + 6, &analogPins[6], 2);
// write 3rd CAN frame to serial
SendCANFrameToSerial(3202, frameData);
// build 4th frame, this is a text extension frame
// only send once at 1000 loops
if (textCounter == 0)
{
SendTextExtensionFrameToSerial(3203, "Hello RealDash, this is Arduino sending some text data");
}
else if (textCounter == 1000)
{
SendTextExtensionFrameToSerial(3203, "Tomorrow's forecast: Lots of sun and 30 degrees centigate");
}
else if (textCounter == 2000)
{
SendTextExtensionFrameToSerial(3203, "Now Playing: Insert your favorite song info here");
}
else if (textCounter == 3000)
{
SendTextExtensionFrameToSerial(3203, "Message from Arduino: All systems running at nominal efficiency");
}
}
void SendCANFrameToSerial(unsigned long canFrameId, const byte* frameData)
{
// the 4 byte identifier at the beginning of each CAN frame
// this is required for RealDash to 'catch-up' on ongoing stream of CAN frames
const byte serialBlockTag[4] = { 0x44, 0x33, 0x22, 0x11 };
Serial.write(serialBlockTag, 4);
// the CAN frame id number (as 32bit little endian value)
Serial.write((const byte*)&canFrameId, 4);
// CAN frame payload
Serial.write(frameData, 8);
}
void SendTextExtensionFrameToSerial(unsigned long canFrameId, const char* text)
{
if (text)
{
// the 4 byte identifier at the beginning of each CAN frame
// this is required for RealDash to 'catch-up' on ongoing stream of CAN frames
const byte textExtensionBlockTag[4] = { 0x55, 0x33, 0x22, 0x11 };
Serial.write(textExtensionBlockTag, 4);
// the CAN frame id number (as 32bit little endian value)
Serial.write((const byte*)&canFrameId, 4);
// text payload
Serial.write(text, strlen(text) + 1);
}
}
void ReadIncomingSerialData()
{
while (Serial.available() > 0)
{
// little bit of extra effort here, since especially Bluetooth connections
// may leave unsent/received data in internal buffer for a long time
// therefore, we cannot be sure that incoming byte stream really starts at
// where we expect it to start.
// read one byte from serial stream
incomingFrame[incomingFramePos++] = Serial.read();
// check the first incoming bytes tag (0x44, 0x33, 0x22, 0x11)
if (incomingFrame[0] != 0x44)
{
// first incoming byte is not 0x44,
// the tag at the beginning of the frame does not match, this is an invalid frame
// just zero the incomingFrame buffer and start expecting first byte again
memset(incomingFrame, 0, 17);
incomingFramePos = 0;
}
if (incomingFramePos >= 17)
{
// frame complete, process it
ProcessIncomingFrame(incomingFrame);
// zero the incomingFrame buffer and start expecting first byte again
memset(incomingFrame, 0, 17);
incomingFramePos = 0;
}
}
}
void ProcessIncomingFrame(const byte* frame)
{
// first four bytes contain set value frame separator bytes, always 0x44,0x33,0x22,x11
// check that first 4 bytes match the tag
if (frame[0] != 0x44 ||
frame[1] != 0x33 ||
frame[2] != 0x22 ||
frame[3] != 0x11)
{
// frame tag does not match, wait for another frame
return;
}
// next four bytes contain set value CAN frame id in little endian form
unsigned long canFrameId = 0;
memcpy(&canFrameId, frame + 4, 4);
// next 8 bytes are the frame data
// ...
// last byte is check byte calculated as sum of previous 13 bytes (ignore overflow)
byte checkByte = 0;
for (int i=0; i<16; i++)
{
checkByte += frame[i];
}
if (frame[16] == checkByte)
{
// checksum match, this is a valid set value-frame:
// the frame payload data is in frame + 8 bytes
HandleIncomingSetValueFrame(canFrameId, frame + 8);
}
}
void HandleIncomingSetValueFrame(unsigned long canFrameId, const byte* frameData)
{
if (canFrameId == 3201)
{
memcpy(&digitalPins, frameData, 2);
memcpy(&analogPins[0], frameData + 2, 2);
memcpy(&analogPins[1], frameData + 4, 2);
memcpy(&analogPins[2], frameData + 6, 2);
#if defined (READWRITE_PINS)
// write digital pins
for (int i=0; i<13; i++)
{
if (i==4)
{
if ((digitalPins & (1 << i)) == HIGH)
{
int output;
int led_value;
output = analogRead(A0);
led_value = map(output, 0, 1023, 255, 120);
analogWrite(i + 1, led_value);
}
//else if ((digitalPins & (1 << i)) != HIGH)
//{
// digitalWrite(i + 1, (digitalPins & (1 << i)) ? HIGH : LOW);
//}
}
else if (i != 4)
{
digitalWrite(i + 1, (digitalPins & (1 << i)) ? HIGH : LOW);
}
}
analogWrite(0, analogPins[0]);
analogWrite(1, analogPins[1]);
analogWrite(2, analogPins[2]);
#endif
}
else if (canFrameId == 3202)
{
memcpy(&analogPins[3], frameData + 0, 2);
memcpy(&analogPins[4], frameData + 2, 2);
memcpy(&analogPins[5], frameData + 4, 2);
memcpy(&analogPins[6], frameData + 6, 2);
#if defined (READWRITE_PINS)
analogWrite(3, analogPins[3]);
analogWrite(4, analogPins[4]);
analogWrite(5, analogPins[5]);
analogWrite(6, analogPins[6]);
#endif
}
}