Stark CMR

MCU / flash: ESP32 (Xtensa LX6 dual-core, 240 MHz); 4 MB flash on CMR v1, 8 MB on v2.

The Stark CMR (SCMR) is a commercially available and CE certified product specifically designed for the Battery Emulator project. It aims to make installs clean, easy, expandable and electrician friendly.

Get the SCMR and other related hardware via the official web shop.

SCMR02 SCMR01

Overview of features~

GPIO	Function
0	FLA push-button — long-press options available
2	Equipment stop input — or SMA inverter contactor enable input (also broken out on the extra header)
4	LED chain data: pixel 0 = status LED, pixels 1–4 = precharge, negative contactor, positive contactor, BMS Power
5	On-board MCP2518FD SDI
12	Second MCP2518FD (GPIO header add-on): CS — JTAG TDI on the header
14	Second MCP2518FD (GPIO header add-on): INT — JTAG TMS on the header
15	Third battery contactors output — JTAG TDO on the header
16	On-board MCP2518FD SCK on Stark CMR v1 (4 MB flash)
17	On-board MCP2518FD SCK on Stark CMR v2 (also available on the extra header when CAN channel 2 is inactive)
18	On-board MCP2518FD CS
19	Second battery contactors output — or HIA4V1 precharge control (also on the extra header)
21	RS485 RX
22	RS485 TX
23	BMS Power output (default 23) — or precharge contactor output (when BMS Power moves to Pin 25)
25	Precharge contactor output (default) — or BMS Power output — or inverter disconnect contactor output — or battery wake-up 1 (WUP1); held across a reset/OTA reboot
26	Native CAN RX
27	Native CAN TX
32	Positive contactor output — or battery wake-up 2 (WUP2)
33	Negative contactor output
34	On-board MCP2518FD SDO
35	On-board MCP2518FD INT

NOTE

BMS Power is always enabled on this board (always_enable_bms_power()).

Power~

Supply voltage (+5VDC - +16VDC) protected with reverse polarity circuitry
Operating current < 300mA @ 3,3VDC when all outputs are activated
USB connection and simultaneous external power supply are compatible
All 3V3 logic with resettable over-current protection
Four individually controllable power outputs, equal to the DC input voltage consisting of:

1 relay channel, 7A continuous, 12A maximum. Located on the main output 1 connector.
3 MOSFET channels, 0,65A continuous, 1,4A maximum with resettable over-current protection.

The MOSFET channels are located on the secondary output connector.
Current specifications are valid at a surrounding temperature of 25°C or below.

Communication~

1 x RS485 channel using Texas Instruments transceiver
1 x CAN channel using Texas Instruments transceiver
1 x CAN/CAN-FD channel using Microchip technology MCP2518FD controller and Texas Instruments transceiver

All of the above protected using GDT/ESD/TVS discrete components

Easily accessible DIP switches for termination on all three lines

SoC~

ESP32-WROOM-32E using ESP32-D0WDR2-V3
Xtensa® dual-core 32-bit LX6 microprocessor, up to 240 MHz
448 KB ROM, 520 KB SRAM, 16 KB SRAM in RTC
Equipped with 8MB Flash and 2MB PSRAM

Status LEDs~

1 x logic power indicator (Blue)
4 x outputs status indicators (Green: GPIO 25, Yellow: GPIO 33, Orange: GPIO 32, Red: GPIO 23)
1 x programmable REG WS2812B (GPIO 4)

All except power indicator available on board as well as on perpendicular plug-in PCB for better visibility

Extra headers~

7 available GPIOs (5 freely usable, 1 bootstrapped, 1 conditioned)
SPI/JTAG header (or used as part of the 6 GPIOs)
Maximum current per GPIO must not exceed 20mA

Physical control / Interaction~

1 x USB-C power and data connector
3 x DIP-switches toggling individual termination resistors for RS585, CAN and CAN/CAN-FD
2 x Momentary switches for SoC manual reset and flash (GPIO-0 to GND) functions
1 x JTAG header

Where can I get one?~

Additional information on the Stark CMR and upcoming related products is available at shop.redispo.se where you also have the option to buy the unit
On the project discord you'll find a thread called "Stark Hardware" where you can chat to Stark CMR users.<br/

You're also welcome to contact Johan directly if you have any questions regarding the hardware.

Documents~

Latest instruction manual SCMR01

Latest instruction manual SCMR02

Installing the software~

Follow the quickstart guide to install the Battery-Emulator software onto the board for the initial setup.

Over the air (OTA) software updates~

When updating this board OTA, be sure to select the software marked for this board. The files will be marked like this, signaling that this is Stark hardware.

BE_vX.Y.Z_StarkCMR.ota.bin

Interfaces~

The board comes with 2 CAN channels, the second one of them being capable of CAN-FD. The board also has an RS485 channel, which can be used for Modbus inverters or RS485 batteries.

The interfaces correspond to the following options in the Battery-Emulator software

CAN-1 -> Native CAN
- CAN 1L (CAN-LOW)
- CAN 1H (CAN-HIGH)
CAN-2 -> Native CAN FD
- CAN 2L (CAN-LOW)
- CAN 2H (CAN-HIGH)
- Note, this channel can be used as classic CAN by enabling "Use CanFD as classic CAN" option
RS485 -> RS485 / Modbus
- RS485 A
- RS485 B

Adding a third CAN channel~

For integrations that need double/triple battery compatibility via CAN, or an additional CAN-FD chanel, you can add an MCP2518FD add-on board via the GPIO expansion header. Connect the wires as following:

IMT to 14
CS to 12
SCK to 17
MISO to 34
MOSI to 5
3.3V to 3.3V
5V to 5V
GND to GND

After connecting the board, you can enable the add-on CAN by configuring it as MCP2518FD (GPIO add-on) to component.

Example, Stark CMR used to control 3x separate Nissan LEAF batteries with one of them being on an add-on MCP2518FD board

Example connection diagram~

This is an example wiring diagram for connecting the Stark CRM, a Nissan Leaf battery pack, a Fronius inverter and an E-stop button (NC). This diagram shows high side switching contactors which is found in most battery packs. I.e. +12V is "fed into" the battery on the dedicated pins to close the contactors.

stark1

Notes: All connections marked GND on the SCMR are joined via the GND plane of the PCB. 5V is the suggested voltage level for the E-stop in this case but it will also work using 12V or 3.3V.

The configuration for the above example would look like this:

stark2

The next wiring diagram shows an example for wiring a Renault Zoe battery. This differs from the previous example as the contactors use low side switching, i.e. the contactors will be closed when the dedicated pins from the contactors on the battery are "shorted to ground".