Archive

IronMaple ESP32‐FRC‐devkit sponsored by JLCPCB

If you are looking for IronMaple ESP32‐FRC‐devkit resources, please switch branch to dev-board.

Code, CAD models: https://github.com/sikaxn/FRC-Custom-CAN-Sensor/tree/dev-board/pcb

Manual: https://github.com/sikaxn/FRC-Custom-CAN-Sensor/wiki/800.-IronMaple-ESP32%E2%80%90FRC%E2%80%90devkit-Manual

Design file: https://oshwlab.com/sikaxn/seal-v2-dev-board

Factory test code: https://studenttechsupport.com/customcanespfw/factory/

Firmware tbd fix

Addressable LED

1. Allow change number of pixel over CAN DONE
2. offline detection on roborio driver DONE

Battery Tracking

1. Indicator Task that use IM dev board RGB LED DONE
2. Better CAN protocol - Allow writing energy form roboRIO by user DONE
3. Better CAN protocol - Allow user to trigger tag rescan over CAN DONE
4. Better CAN protocol - More status feedback from ESP32 (tag write error) DONE
5. Better CAN protocol - Empty message upon startup DONE
6. Allow change CAN Device Number using web tool DONE
7. APP improvment - init new serial number follow BEST protocol (or disable this in setting)
8. APP improvment - App should not be set as default NFC app on Android

IM ESP Devkit demo

1. Bugfix - Change CAN Device Number using web tool currently not working. DONE
2. Maybe merge Addressable LED with it.

Battery Tracking + addressable LED combined firmware

1. New firmware that combine those two together. DONE

Custom CAN sensor with roboRIO

Please also check out the WiKi section for more documentation!

https://github.com/sikaxn/FRC-Custom-CAN-Sensor/wiki

Some resources in another branch

This repo need some cleanup. Will do later.

https://github.com/sikaxn/FRC-Custom-CAN-Sensor/tree/dev-board

IronMaple ESP32‐FRC‐devkit sponsored by JLCPCB

If you are looking for IronMaple ESP32‐FRC‐devkit resources, please switch branch to dev-board.

Code, CAD models: https://github.com/sikaxn/FRC-Custom-CAN-Sensor/tree/dev-board/pcb

Manual: https://github.com/sikaxn/FRC-Custom-CAN-Sensor/wiki/800.-IronMaple-ESP32%E2%80%90FRC%E2%80%90devkit-Manual

Design file: https://oshwlab.com/sikaxn/seal-v2-dev-board

Factory test code: https://studenttechsupport.com/customcanespfw/factory/

Web firmware flasher

Pre built ESP32 firmware for Battery RFID Tracker and Addressable LED Controller. Just Chrome, USB and flash.

https://studenttechsupport.com/customcanespfw/

Web flasher source code: https://github.com/sikaxn/sikaxn.github.io/tree/master/customcanespfw

ChiefDelphi Thread

https://www.chiefdelphi.com/t/custom-can-sensor-some-good-progress/501764

Video

Potentiometer analog input https://www.youtube.com/watch?v=bEm6USGRP-E

LED (pin 13) digital output https://www.youtube.com/shorts/q937u09llhw

roboRIO heartbeat (look at the LED blinking while enabled) https://www.youtube.com/shorts/c1ieu9o8Lzo

⚠️ Disclaimer

This project is for demo and under work. Faulty CAN frame could bring entire CAN bus down.

This project use AI generated content.

What's in this repository:

1. [Arduino Mega] Digital Analog bi-directional (Docs / Arduino Firmware / roboRIO / RIO Simulator)
2. [Arduino Mega] REV Colour sensor (Docs / Arduino Firmware / roboRIO) (this share the same roboRIO code with the first one)
3. [Arduino Mega] LCD Screen (Arduino Firmware / roboRIO / RIO Simulator)
4. NOT FRC LEGAL [ESP32] Robomaster motor gateway (dual CAN on ESP32) (Arduino Firmware / roboRIO)
5. NOT FRC LEGAL Robomaster DT7 Remote on CAN (Arduino Firmware / roboRIO)
6. [ESP32] Battery Tracking System (Arduino Firmware / roboRIO / Android APP / Docs)
7. [ESP32] ToF using 4 VL53L1X (Docs / Arduino Firmware / roboRIO / UITool / ROI Calculator Tool)
8. [ESP32] Addressable LED Controller (Arduino Firmware / roboRIO)
9. [ESP32] Battery Tracking (Arduino Firmware / roboRIO) / Docs
10. [ESP32] Battery Tracking LF (Arduino Firmware / roboRIO) / Docs
11. [ESP32] REV and Andymark Colour sensor (Arduino Firmware / roboRIO) / Docs

Important reminder of ESP32 radio:

Per FRC Game Manual (2025) R707 and E301, Wi-Fi radio should not be used within competition area and Bluetooth radio should not be used if robot is competing on the field. As for now, none of the code utilizing ESP32 have any wireless capability. However, if further update enabled this capability, the use of such device and software should be carefully planned and coordinated to stay in compliance with the game manual.

How FRC CAN bus works

The 'CAN ID' we talked about when setting up motor controllers (Spark, Kraken, PDP, etc) is a number from 0-63. This is not the CAN identifier (message ID) used in CAN data layer. FRC Use a very specific scheme outlined in FRC CAN specification to convert certain information to CAN identifier. All device connected to roboRIO must follow this scheme when determine what ID to send data to and read form.

https://docs.wpilib.org/en/stable/docs/software/can-devices/can-addressing.html#requirements-for-frc-can-nodes

CAN identifier is calculated from device ID (device type ID), manufacturer ID, API ID (in the documentation it talked about API Class and Index but doesn't matter and it is just a suggestion. Each device will have its unique API ID designed for its use) and device number (0-63 as the traditional 'CAN ID' we talked about in FRC).

You must generate your CAN identifier (message ID) using this very specific way. A device will have multiple CAN message sent to and from roboRIO (and possibly to other non-roboRIO device). These different messages will share the same device type ID, manufacturer ID and device number. API ID will change based on use.

Update

1. REVCOlourSensorV3 Arduino sketch has been updated to do conversion in code. In addition, rm_dt7 is added to handle Robomaster / DJI DT7 Remote with DR16. This is not legal to use in FRC. However you could still take a look at these conversion.

// === CAN Constants ===
#define DEVICE_TYPE_ID        0x0A  //DONOT CHANGE
#define MANUFACTURER_ID  0x08  //DONOT CHANGE
#define DEVICE_NUMBER    33  // Device Number 0-63
#define STATUS_API_ID        0x180
#define COLOR_SENSOR_API_ID  0x184
#define CONTROL_API_ID       0x190
#define HEARTBEAT_ID         0x01011840

uint32_t makeCANMsgID(uint8_t deviceID, uint8_t manufacturerID, uint16_t apiID, uint8_t deviceNumber) {
  return ((uint32_t)(deviceID & 0xFF) << 24) |
         ((uint32_t)(manufacturerID & 0xFF) << 16) |
         ((uint32_t)(apiID & 0x3FF) << 6) |
         (deviceNumber & 0x3F);
}

2. An ID converter script is added. see below for usage.

3. DO NOT change DEVICE_TYPE_ID and MANUFACTURER_ID as this will result roboRIO code stop working.

Message ID Generator GUI Tool

A minimal Tkinter application for converting between FRC 29-bit CAN IDs and their four fields.

CANDbg Message Viewer tool

A minimal Tkinter application viewing CAN messages using python-can.

Support Ctrl + C to copy message and roboRIO heartbeat decoding.