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DALY CAN Communications Protocol

Version: 1.0
Date: 2019-06-11
Author: Dongguan Daly Electronics Co., Ltd

Version History

Serial Num Description Date Version
1 Initial version 2019.06.11 V1.0

1. Physical Layer

  • Interface: CAN
  • Baud Rate: 250K

2. Communication Format

2.1 Basic Timing

  • All messages are initiated by the host.
  • All slaves receive messages and respond only if the slave address matches.
  • Only matched slaves are allowed to return data to the host.

2.2 Address Assignment

Module Address
BMS Master 0x01
Bluetooth App 0x80
GPRS 0x20
Upper Computer 0x40

2.3 CAN Communication Format

2.3.1 Host → Slave

CAN ID Data
Priority + Data ID + BMS Address + PC Address
0x18 10 01 40		 8 bytes

2.3.2 Slave → Host

CAN ID Data
Priority + Data ID + PC Address + BMS Address
0x18 10 40 01		 8 bytes

3. Communication Content Information

Each message uses a unique Data ID.

0x90 - Total Voltage, Current, SOC

  • Send: Byte0~7: Reserved
  • Receive:
  • Byte0~1: Cumulative total voltage (0.1 V)
  • Byte2~3: Gather total voltage (0.1 V)
  • Byte4~5: Current (offset 30000, 0.1 A)
  • Byte6~7: State of Charge (SOC, 0.1%)

0x91 - Maximum and Minimum Voltage

  • Send: Byte0~7: Reserved
  • Receive:
  • Byte0~1: Max cell voltage (mV)
  • Byte2: Cell number with max voltage
  • Byte3~4: Min cell voltage (mV)
  • Byte5: Cell number with min voltage

0x92 - Maximum and Minimum Temperature

  • Send: Byte0~7: Reserved
  • Receive:
  • Byte0: Max temperature (offset 40, °C)
  • Byte1: Cell number with max temperature
  • Byte2: Min temperature (offset 40, °C)
  • Byte3: Cell number with min temperature

0x93 - MOSFET Charge/Discharge Status

  • Send: Byte0~7: Reserved
  • Receive:
  • Byte0: State (0 = stationary, 1 = charge, 2 = discharge)
  • Byte1: Charge MOS status
  • Byte2: Discharge MOS status
  • Byte3: BMS life (0–255 cycles)
  • Byte4~7: Remaining capacity (mAh)

0x94 - Status Information 1

  • Send: Byte0~7: Reserved
  • Receive:
  • Byte0: Number of battery strings
  • Byte1: Number of temperature sensors
  • Byte2: Charger status (0 = disconnected, 1 = connected)
  • Byte3: Load status (0 = disconnected, 1 = connected)
  • Byte4: Bitmask of DI/DO states:
    • Bit 0–3: DI1–DI4
    • Bit 4–7: DO1–DO4
  • Byte5~7: Reserved

0x95 - Cell Voltage (1~48)

  • Send: Byte0~7: Reserved
  • Receive:
  • Voltage for each cell is 2 bytes (1 mV)
  • Max 96 bytes sent in 16 frames
  • Byte0: Frame number (0–15, 0xFF = invalid)
  • Byte1~6: Cell voltages
  • Byte7: Reserved

0x96 - Cell Temperature (1~16)

  • Send: Byte0~7: Reserved
  • Receive:
  • Each temperature is 1 byte (offset 40, °C)
  • Max 21 bytes in 3 frames
  • Byte0: Frame number (starts at 0)
  • Byte1~7: Temperatures

0x97 - Cell Balance State (1~48)

  • Send: Byte0~7: Reserved
  • Receive:
  • Bit0–47: 0 = Closed, 1 = Open (balance state for cells 1–48)
  • Bit48–63: Reserved

0x98 - Battery Failure Status

  • Send: Byte0~7: Reserved
  • Receive:
Byte Bits Description
0 0–7 Cell/Sum voltage high/low levels
1 0–7 Charge/Discharge temperature alarms
2 0–7 Overcurrent, SOC level alarms
3 0–7 Voltage/temperature difference alarms
4 0–7 MOS temp & circuit errors
5 0–7 Hardware errors (AFE, EEPROM, RTC, etc.)
6 0–7 Module/circuit protection faults
7 0–7 Fault code

See detailed bit mapping for each fault category.

Notes

  • All values using offsets (