Secondary Serial IO interface

Overview

The Arduino Mega2560 version of Speeduino supports the use of Serial3 for supplemetry IO.The proposed STM32 and Teensy3.5 versions use Serial2 . On a Mega 2560 Serial3 can be found on the board at pins 14 and 15.The connection speed is 115200baud.

Settings

• Enable Secondary IO interface - To enable use of the Secondary io interface it must be enabled in TunerStudio.

Dependant on if CAN_COMMANDS have been enabled will vary the type of dropdown menu you will see

With CAN_COMMANDS disabled

With CAN_COMMANDS enabled

• Secondary IO options - Again dependant on if CAN_COMMANDS have been enabled will vary what options you have to enable Secondary serial.

With CAN_COMMANDS disabled

With CAN_COMMANDS disabled

• Enable options
• 1. Disabled
• 2. Enabled Secondary IO via Serial port
• 3. Enabled Secondary IO via canbus (this option will only be available when CAN_COMMANDS are enabled

How to use it

Depending on if the secondary port is a simple serial port or is a canbus port there are several things that the Secondary io interface is capable of.

• 1. Retreive the current realtime data just as is sent to TunerStudio.
• 2. Read in the Analog data values from 8 remote sensors.
• 3. Acivate External Outputs(coming soon!)

Retrieve realtime data

To get Speeduino to send out the realtime data to your device connected on a Secondary Serial IO port you must send either an "A" or an "r" to it.

• Send an "A"

If you send an "A" to the port it will reply with ,

"A" confirming the received instruction (sent as 0x41 in hex),

The port will now transmit a single byte in hex ,this is the number of bytes it is about to send .This is currently 0x39 (57 in decimal).

The port will then transmit ALL the realtime data.

• Send an "r"

if you send an "r" to the port you must also send 4 further bytes immediately after the "r". These are a 2 byte offset and a 2 byte length. the offset is the position in he realtime list you want the data returned to start from and the 2 byte length is the number of bytes you want returned. the bytes are sent LSB first . The port will reply with ,

"r" confirming the received instruction (send as 0x72 in hex) ,

The port will now transmit a single byte in hex ,this is the number of bytes it is about to send confirming what was requested.

The port will then transmit the realtime data requested starting at the byte position sent for the number of bytes length.

• The Realtime Data List

As of 02/05/2017 the data list is as follows

0 - currentStatus.secl

   secl is simply a counter that increments each second

1 - currentStatus.squirt

   Squirt Bitfield

2 - currentStatus.engine

   Engine Status Bitfield

3 - (byte)(divu100(currentStatus.dwell))

   Dwell in ms * 10

4 - (byte)(currentStatus.MAP >> 1)

   map value is divided by 2

5 - (byte)(currentStatus.IAT + CALIBRATION_TEMPERATURE_OFFSET)

   mat

6 - (byte)(currentStatus.coolant + CALIBRATION_TEMPERATURE_OFFSET)

   Coolant ADC

7 - currentStatus.tpsADC

   TPS (Raw 0-255)

8 - currentStatus.battery10

   battery voltage

9 - currentStatus.O2;

   primary O2

10 - currentStatus.egoCorrection

   Exhaust gas correction (%)

11 - currentStatus.iatCorrection

   Air temperature Correction (%)

12 - currentStatus.wueCorrection

   Warmup enrichment (%)

13 - lowByte(currentStatus.RPM)

   rpm LB

14 - highByte(currentStatus.RPM)

   rpm HB

15 - currentStatus.TAEamount

   acceleration enrichment (%)

16 - currentStatus.baro

   Barometer value

17 - currentStatus.corrections

   Total GammaE (%)

18 - currentStatus.VE

   Current VE 1 (%)

19 - currentStatus.afrTarget

   chosen afr target

20 - (byte)(currentStatus.PW1 / 100)

   Pulsewidth 1 multiplied by 10 in ms. Have to convert from uS to mS

21 - currentStatus.tpsDOT

   TPS DOT

22 - currentStatus.advance

   Current spark advance

23 - currentStatus.TPS

   TPS (0% to 100%)

24 - lowByte(currentStatus.loopsPerSecond)

   loops per second LB

25 - highByte(currentStatus.loopsPerSecond)

   loops per second HB

26 - lowByte(currentStatus.freeRAM)

   freeRam LB

27 - highByte(currentStatus.freeRAM)

   freeRam HB

28 = currentStatus.batCorrection

    Battery voltage correction (%)

29 = currentStatus.spark

    Spark related bitfield

30 = currentStatus.O2_2

    Second O2

31 = lowByte(currentStatus.rpmDOT)

    rpmDOT must be sent as a signed integer

32 = highByte(currentStatus.rpmDOT)

    rpmDOT HB

33 = currentStatus.ethanolPct

    Flex sensor value (or 0 if not used)

34 = currentStatus.flexCorrection

    Flex fuel correction (% above or below 100)

35 = currentStatus.flexIgnCorrection

    Ignition correction (Increased degrees of advance) for flex fuel

36 = getNextError()

    Error codes

37 = currentStatus.boostTarget

    Target boost pressure

38 = currentStatus.boostDuty

    current pwm boost dutycycle

39 = currentStatus.idleLoad

    idleload

40 = currentStatus.testOutputs

    testoutputs bitfield

41 = lowByte(currentStatus.canin[0])

    Can input 0 LB     

42 = highByte(currentStatus.canin[0])

    Can input 0 HB

43 = lowByte(currentStatus.canin[1])

    Can input 1 LB

44 = highByte(currentStatus.canin[1])

    Can input 1 HB

45 = lowByte(currentStatus.canin[2])

    Can input 2 LB

46 = highByte(currentStatus.canin[2])

    Can input 2 HB

47 = lowByte(currentStatus.canin[3])

    Can input 3 LB 

48 = highByte(currentStatus.canin[3])

    Can input 3 HB

49 = lowByte(currentStatus.canin[4])

    Can input 4 LB

50 = highByte(currentStatus.canin[4])

    Can input 4 HB

51 = lowByte(currentStatus.canin[5])

    Can input 5 LB

52 = highByte(currentStatus.canin[5])

    Can input 5 HB

53 = lowByte(currentStatus.canin[6])

    Can input 6 LB

54 = highByte(currentStatus.canin[6])

    Can input 6 HB

55 = lowByte(currentStatus.canin[7])

    Can input 7 LB

56 = highByte(currentStatus.canin[7])

    Can input 7 HB

Read external analog data

To get Speeduino to read analog data over Serial3 you must enable it. this is done in TS on an per channel basis.

You then set the input parameter group,input start byte number and input parameter number of bytes according to the sensor being accessed. Once enabled and configured Speeduino will periodically poll for that device on Serial3

The IO on Serial3 follows a similar protocol format to that of J1939 , this makes looking up a sensors configuration details quite straight forward.

Example 1:

  Sensor type : Engine oil Temperature
  parameter group = 65262
  start byte = 1
  number of bytes = 1

Example 2:

  sensor type : Engine oil pressure
  parameter group = 65263
  start byte = 4
  number of bytes = 1

Example 3:

  sensor type : Exhaust temperture port 1
  parameter group = 65187
  start byte = 1
  number of bytes = 2

Example 4:

  sensor type : Exhaust temperature port 3
  parameter group = 65263
  start byte = 5
  number of bytes = 2

Using Example 1 this is how to get your remote device to reply to the request from Speeduino for data.

Speeduino will send an "R"

Followed by the device parameter group number(this is sent in two bytes LSB first)

Speeduino will now await the response.

You must first send an "G" ,

Then send 8 bytes of data. The Data you wish to send is placed in bytes 0 and 1 (LSB and MSB respectively)if it is two bytes long or in byte 0 if it is only a single byte long .

The value sent is readable in Tunerstudio using the CanIN gauges