Skip to content

Latest commit

 

History

History
56 lines (46 loc) · 4.38 KB

Replace_Elm327_BT_Mini_Firmware.md

File metadata and controls

56 lines (46 loc) · 4.38 KB
Raw

Replace ELM327 BT V1.5 HW: V01_M_V2.3 adapter firmware (or equivalent)

This chapter describes how to replace the ELM327 BT V1.5 HW: V01_M_V2.3 adapter PIC18F25K80 firmware and YC1021 BT settings.

Requirements:

ELM327 BT V1.5 HW: V01_M_V2.3 board connections:

ELM327 BT V1.5 HW: V01_M_V2.3 board programming connections big

ELM327 BT V1.5 HW: V1.5_S_V2.0 board connections:

ELM327 BT V1.5 HW: V1.5_S_V2.0 board programming connections big

Step1: Program the YC1021 BT settings

  • Connect your EZP2010 or TL866II Plus or CH341A Eeprom programmer clip on to the SOIC8 (150mil) 24C32 / 24C64 eeprom chip, take note of orientation (red wire of clipon goes to red annotated 24C32 pin1)

  • Do a full read with eeprom powered from programmer (do not apply power from obd side).
    It's recommended that you disconnect VCC pin 8 of the 24C32 chip first!
    It may take a few read tries to get the full dump correctly, if the first 0x80 bytes only contain 0xFF your read is incorrect.

  • There are two EEPROM layout variants with an data offset of 0xB (original files original_v1_.bin and original_v2_.bin)

  • EEPROM 24C32 layout variant 1 / 2:

    • BT address: 0x0F93 / 0x0F88 (6 bytes, normally keep unchanged)
    • BLE address: 0x0F99 / 0x0F8E (6 bytes, normally keep unchanged)
    • PinCode: 0x0F9F / 0x0F94, 1 byte length (max 15) and 15 byte PIN ASCII chars
    • BT 2.x name: 0x0FAF / 0x0FA4, 1 byte length (max 32) and 32 byte BT name ASCII chars
    • BLE name: 0x0FD0 / 0x0FC5, 1 byte length (max 24) and 32 byte BLE name ASCII chars
    • BaudRate: 0x0FF0 / 0x0FE5 (2 bytes, low byte first); default value: 0x04E2 is 38400 baud (for default PIC firmware), change to 0x01A1 for 115200 baud (for def115200 or yc1021 firmware)

  • EEPROM 24C64 layout variant:

    • BT address: 0x18E3 (6 bytes, normally keep unchanged)
    • BLE address: 0x18E9 (6 bytes, normally keep unchanged)
    • PinCode: 0x18EF, 1 byte length (max 15) and 15 byte PIN ASCII chars (for some unknown reason some have 0000 but the adapter accepts only 1234)
    • BT 2.x name: 0x1900, 1 byte length (max 32) and 32 byte BT name ASCII chars
    • BLE name: 0x1920, 1 byte length (max 24) and 32 byte BLE name ASCII chars
    • BaudRate: 0x1940 (2 bytes, low byte first); default value: 0x04E2 is 38400 baud (for default PIC firmware), change to 0x01A1 for 115200 baud (for def115200 or yc1021 firmware)

  • Optionally you could use preconfigured settings file modified_v1.bin from the latest binary.

  • Write the changed binary back to the 24C32/24C64A eeprom (again powered from programmer, not from obd side).

Step2: Program the PIC18F25K80

  • Connect your PicKit 3/4 to MCLR, PGD, PGC, GND (Vss) and 5V (Vcc) (take care, do not apply power from PicKit 3/4)
  • Power the Elm327 adapter (from obd side)
  • From subdirectory CanAdapterElm select either default (baudrate 38400), def115200 (baudrate 115200) or yc1021 firmware (recommended for non standard LED allocation) (baudrate 115200), always use CanAdapterElm.X.production.unified.hex for this first upload
  • Flash the selected firmware to the PIC18F25K80

Step3: Testing

  • Power the Elm327 adapter
  • Connect to XXYYZZ BT device and pair with it (standard pincode: 1234)
  • Connect to the COM port assigned to your BT device
  • When sending strings to the adapter you should at least get an echo from the adapter, otherwise there is a problem with the connections.
    You could test reading the ignition pin with the following command (hex values):
    82 F1 F1 FE FE 60
    The response is (additionally to the echo):
    82 F1 F1 FE <state> <checksum> with state bit 0 set to 1 if ignition is on.