Arduino-powered digital dashboards... For kittens!
This is designed to receive data over CAN BUS from a MegaSquirt and present it on a Nextion LCD display.
It also allows you to use the Arduino's analog-in pins as extra analog inputs for the MegaSquirt.
This software is designed for:
- Arduino Uno
- Seeed Studio CAN-BUS shield v1.2
- Nextion NX4024T032_011R display
- Arduino IDE 1.6.6
- MCP_CAN_lib
- MegaSquirt III, firmware 1.4.0
These exact versions are known good, but other variants probably work.
This depends on MCP_CAN_lib to communicate with the CAN BUS chip. To install it on Linux:
cd ~/Arduino
git clone https://github.com/coryjfowler/MCP_CAN_lib.git
cd MCP_CAN_lib
git checkout eecf231fb0b1e594086f6212dfd6b643eca1b8d9
Now start the Arduino IDE and open dash-kitten.ino; click Upload and it should build and run.
Plan A:
- Connect the display to a TTL-serial cable
- Open dash-kitten.hmi in the Nextion GUI
- click upload
- If the transfer fails your display may be bricked. Proceed to Plan B.
Plan B:
- Copy dash-kitten.tft as the only file on a FAT32-formatted micro-SD card
- Click it into the SD slot
- Power on
- Find out that the Nextion display is really picky about which SD cards work
- Find another micro-SD card
- GOTO 10
Stack the CAN-BUS shield on the Arduino, and connect the CAN-high and CAN-low pins to your MS3.
Connect the Nextion display as follows:
- Black - GND
- Red - 5v
- Yellow - Digital pin 4
- Blue - Digital pin 5
To send data from the MegaSquirt to the DashKitten, go to CAN-bus/Testmodes, then CAN Realtime Data Broadcasting 1/2/3/4. We're using these settings:
| Frequency | IDs |
|---|---|
| 50Hz | 00, 01, 02, 03, 18 |
| 20Hz | 04, 13, 17, 42, 51, 52 |
| Off | Everything else |
To send analog measurements from the DashKitten to the MegaSquirt, go to CAN-bus/Testmodes, then CAN Receiving. Configure the channels to be:
| Local Variable / Channel | Identifier (decimal) | Offset | Size | Multiply | Divide | Add |
|---|---|---|---|---|---|---|
| CAN ADC01 | 32 | 0 | B2U | 1 | 1 | 0 |
| CAN ADC02 | 32 | 2 | B2U | 1 | 1 | 0 |
| CAN ADC03 | 32 | 4 | B2U | 1 | 1 | 0 |
| CAN ADC04 | 32 | 6 | B2U | 1 | 1 | 0 |
| CAN ADC05 | 33 | 0 | B2U | 1 | 1 | 0 |
| CAN ADC06 | 33 | 2 | B2U | 1 | 1 | 0 |
| CAN ADC07 | 33 | 4 | B2U | 1 | 1 | 0 |
| CAN ADC08 | 33 | 6 | B2U | 1 | 1 | 0 |
There appears to be a bug in MegaSquirt v1.4.0: If the sensor's value exceeds 3276 it will be corrupted. This appears to be a bug in the MS firmware where values are being multiplied by 10 internally (probably fixed-decimal), and being handled as signed values even though they shouldn't. The Arduino Uno's ADC will only output 0-1023 so if you use Multiply=1 Divide=1 it will be fine. Multiply=3 Divide=1 will still be fine (max 3069), but Multiply=4 Divide=1 will cause an overflow into negative numbers. I haven't tried, but Some other models of Arduino such as the Zero have a 12-bit ADC and may have problems even with Multiply=1.
Next go to Advanced Engine, then Generic Sensor Inputs, and assign the CAN ADCs to generic sensors:
| Sensor | Source | Field Name | Transformation |
|---|---|---|---|
| 09 | CAN ADC01 | Sensor 09 | Raw |
| 10 | CAN ADC02 | Sensor 10 | Raw |
| 11 | CAN ADC03 | Sensor 11 | Raw |
| 12 | CAN ADC04 | Sensor 12 | Raw |
| 13 | CAN ADC05 | Sensor 13 | Raw |
| 14 | CAN ADC06 | Sensor 14 | Raw |
| 15 | CAN ADC07 | Sensor 15 | Raw |
| 16 | CAN ADC08 | Sensor 16 | Raw |
You can configure the Field Name to be anything, such as "Oil Pressure". This is what will show up in the logs.
GPL v2