CHESTER-X13
The CHESTER-X13 is a CAN Bus extension module with CAN FD support for the CHESTER platform.
Module Overview
CHESTER-X13 provides a CAN / CAN FD interface based on the MCP2518FD external CAN controller, which communicates with the CHESTER mainboard over SPI. An on-board TCAN3413 transceiver drives the physical bus, and the CANH / CANL lines are brought out to the terminal block. On-board bus-termination resistors are provided but disconnected by default, so the module can sit anywhere on the bus.
The module can run directly from the CHESTER mainboard. Alternatively, an external 5-28 VDC line on +VIN feeds the on-board TPS62933 step-down converter, whose fixed 5 V output powers the CHESTER mainboard. Schottky diodes (PMEG6010ELR) protect the input. An interrupt output signals the CHESTER mainboard when the CAN controller requires attention.
Key Features
- CAN & CAN FD: Wired connectivity based on the MCP2518FD CAN controller.
- SPI Host Interface: Connects to the CHESTER mainboard over SPI.
- On-board Transceiver: TCAN3413 transceiver drives the physical CAN bus.
- Selectable Bus Termination: On-board ~120 Ω termination, disconnected by default.
- Flexible Power: Runs from the CHESTER mainboard, or from an optional 5-28 VDC line on +VIN.
- Input Protection: Schottky diodes (PMEG6010ELR) on the power input.
- Interrupt Output: Dedicated interrupt line to the CHESTER mainboard.
Typical Applications
- Industrial CAN Networks: Connecting CHESTER to a CAN / CAN FD bus.
- Machinery & Equipment Monitoring: Reading data from equipment that exposes a CAN interface.
- Mobile Machinery & Vehicles: Telemetry from agricultural, construction, and other mobile machinery.
- Energy & Power Systems: Monitoring generators, inverters, and battery systems with a CAN interface.
- Retrofit Data Acquisition: Tapping data from an existing CAN bus.
Technical Specifications
| Parameter | Value |
|---|---|
| Interface Type | CAN / CAN FD |
| Bit Rate | Up to 1 Mbit/s (classic CAN), up to 5 Mbit/s (CAN FD) |
| CAN Controller | MCP2518FD (external, SPI) |
| CAN Transceiver | TCAN3413 |
| Host Interface | SPI |
| Bus Termination | On-board ~120 Ω, disconnected by default |
| Power Input (+VIN) | 5-28 VDC (optional external supply) |
| Power Output (+V) | Fixed 5 V, powers the CHESTER mainboard |
| Bus Output | CANH / CANL on the terminal block |
| Board Interface | Castellated holes on two opposite edges, soldered to the CHESTER mainboard |
| Hardware Revision | R1.2 |
Key Components
| Component | Part Number | Description |
|---|---|---|
| CAN Controller | MCP2518FD | External CAN FD controller with SPI interface |
| CAN Transceiver | TCAN3413 | CAN FD transceiver (physical bus interface) |
| DC-DC Converter | TPS62933 | Step-down converter, 5-28 VDC input |
| Input Protection | PMEG6010ELR | Schottky barrier diodes for input protection |
Pin Configuration
The module uses a standardized header layout compatible with CHESTER extension slots.
The pin configuration shown is for the CHESTER-M CGLS mainboard.
CHESTER-X13 Connector Pinout
| Pin | Signal | Type | Description |
|---|---|---|---|
| 1 | INT | Output | Interrupt output to the CHESTER mainboard |
| 2 | RH | CAN Termination | Termination tap for CANH (connect to CANH to enable the on-board termination) |
| 3 | CANH | CAN Bus | CAN bus line, high |
| 4 | CANL | CAN Bus | CAN bus line, low |
| 5 | RL | CAN Termination | Termination tap for CANL (connect to CANL to enable the on-board termination) |
| 6 | GND | Ground | System ground reference |
| 7 | GND | Ground | System ground reference |
| 8 | +VIN | Power Input | Optional external DC input to the on-board step-down (5-28 VDC) |
The module can run directly from the CHESTER mainboard. When an external 5-28 VDC supply is connected to +VIN (Pin 8), the on-board TPS62933 step-down converter produces a fixed 5 V that powers the CHESTER mainboard.
Host Interface (SPI)
Unlike most CHESTER-X modules (which use I²C), CHESTER-X13 communicates with the CHESTER mainboard over SPI. The MCP2518FD controller is driven through the module slot's GP pins:
| CHESTER-X pin | SPI function | MCP2518FD signal |
|---|---|---|
| GP0 | SCLK | SCK |
| GP1 | MOSI | SDI |
| GP2 | MISO | SDO |
| GP3 | CS | NCS |
The MCP2518FD interrupt output (INT) is routed to the module's INT terminal (pin 1). See the Interrupt Pin subsection below.
Interrupt Pin
The MCP2518FD signals events (such as a received CAN frame) on its interrupt output, which is brought out to the module's INT terminal (pin 1). This interrupt must be wired to the CHESTER mainboard's INT terminal so the mainboard can detect it. On the CHESTER-M CGLS mainboard, add a jumper wire from the extension module's terminal block to the mainboard's INT terminal. The wiring below is shown for a module in slot B; a module in another slot connects to that slot's INT terminal the same way.
- Example: interrupt wiring for a module in slot B (CHESTER-M CGLS).
CAN Bus Connection
The CAN bus is wired directly to the terminal-block pins CANH (pin 3) and CANL (pin 4). Use twisted-pair cable with a 120 Ω characteristic impedance, wire the bus as a linear (daisy-chain) topology — avoid star layouts and long stubs — and keep any untwisted wiring at the terminal block as short as possible.
The CAN interface is not galvanically isolated, so all nodes must share a common ground reference. Connect the bus GND to one of the terminal-block GND pins (pin 6 or 7).
Termination Resistors
A CAN bus must be terminated with a 120 Ω resistor between CANH and CANL at both physical ends of the bus. CHESTER-X13 provides an on-board termination that is disconnected by default (a node in the middle of the bus must not be terminated).
Enable it only when the module sits at the end of the bus by connecting CANH to RH (pin 3 to pin 2) and CANL to RL (pin 4 to pin 5) on the terminal block.
Enclosure Feed-Through
Two options bring the CAN cable into the enclosure:
- Cable gland (default): route the CAN conductors through a cable gland in the enclosure wall and wire them to the terminal block.
- Panel-mount connector (on request): an external connector in the enclosure wall lets the user plug in the CAN cable, with no loose wiring inside. Available on request.
Compatible CHESTER Configurations
The CHESTER-X13 module can be used with various CHESTER mainboard configurations. Below are examples of compatible setups:
CHESTER-M (CGLS)
CHESTER-C4
CHESTER SDK usage
CHESTER-X13 can be used as part of the CHESTER SDK using the ctr_x13_a and ctr_x13_b shields, or hardware-chester-x13-a and hardware-chester-x13-b Project Generator features.
Schematic Diagrams
The complete schematic — covering the main page, the CAN interface, and the power supply — is available as a PDF:
Module Drawing
