Zelos Unified Diagnostic Services (UDS) Extension

A Zelos extension implementing UDS (ISO 14229) diagnostic protocol over CAN with ISO-TP transport, built with the Zelos SDK.

Features

• UDS Services: Session Control, Read/Write Data By Identifier, ECU Reset, Routine Control, I/O Control, Tester Present, DTC Reading/Clearing, Security Access, Firmware Flashing
• CAN Integration: ISO-TP transport, configurable interfaces (socketcan, PCAN, Kvaser, Vector)
• Zelos Integration: Interactive actions via Zelos App
• CLI: Execute UDS transactions programmatically from the CLI

Configuration

Configure via Zelos App settings or config.json:

Setting	Default	Description
interface	socketcan	CAN interface (socketcan, pcan, kvaser, vector)
channel	can0	CAN channel/device
bitrate	500000	CAN bitrate (bps)
tx_id	0x7E0	Tester CAN ID
rx_id	0x7E8	ECU CAN ID

Advanced settings (optional):

• request_timeout, p2_timeout, p2_star_timeout - UDS timeouts
• isotp_stmin, isotp_blocksize - ISO-TP flow control
• isotp_tx_padding, isotp_rx_padding, isotp_padding_value - Frame padding

See config.schema.json for complete schema.

UDS Protocol Reference

Supported services per ISO 14229:

Service	ID	Description
DiagnosticSessionControl	0x10	Change diagnostic session
ECUReset	0x11	Reset ECU
ClearDiagnosticInformation	0x14	Clear diagnostic trouble codes
ReadDTCInformation	0x19	Read diagnostic trouble codes
ReadDataByIdentifier	0x22	Read data by DID
SecurityAccess	0x27	Request security access (seed/key)
WriteDataByIdentifier	0x2E	Write data by DID
InputOutputControlByIdentifier	0x2F	Control I/O signals
RoutineControl	0x31	Control diagnostic routines
RequestDownload	0x34	Initiate firmware download
TransferData	0x36	Transfer firmware data blocks
RequestTransferExit	0x37	Finalize firmware transfer
TesterPresent	0x3E	Keep session alive

Standard CAN IDs

ID Range	Purpose
0x7DF	Functional (broadcast) request
0x7E0-0x7E7	Physical request IDs
0x7E8-0x7EF	Physical response IDs

Common Negative Response Codes

Code	Name	Description
0x11	serviceNotSupported	Service not supported in current session
0x13	incorrectMessageLengthOrInvalidFormat	Invalid message format
0x22	conditionsNotCorrect	Preconditions not met
0x31	requestOutOfRange	Parameter out of range
0x33	securityAccessDenied	Security access required
0x78	requestCorrectlyReceived-ResponsePending	Request pending

Links

• Zelos Documentation
• Zelos SDK Guide
• ISO 14229 Specification
• udsoncan Library
• python-can Documentation

CLI Usage

The extension includes a command-line interface for executing UDS transactions. No installation required - just use uv run:

Tip: Run pip install . to install and use zelos-extension-uds <args> from anywhere.

# Change to extended diagnostic session
uv run main.py session --txid 7E0 --rxid 7E8 --type extended

# Read VIN (DID 0xF190)
uv run main.py read --txid 7E0 --rxid 7E8 --id F190

# Write data
uv run main.py write --txid 7E0 --rxid 7E8 --id 1234 --data 01020304

# Read DTCs
uv run main.py dtc --txid 7E0 --rxid 7E8

# Clear DTCs
uv run main.py clear --txid 7E0 --rxid 7E8

# Request security seed
uv run main.py security --txid 7E0 --rxid 7E8 --level 1 --seed

# Send security key
uv run main.py security --txid 7E0 --rxid 7E8 --level 1 --key 01020304

# ECU reset
uv run main.py reset --txid 7E0 --rxid 7E8 --response-required --type hard

# Flash firmware
uv run main.py flash --txid 7E0 --rxid 7E8 --file firmware.bin --address 08000000

# Start routine
uv run main.py routine --txid 7E0 --rxid 7E8 --id 0203 --control start --data 0102

# I/O control
uv run main.py io --txid 7E0 --rxid 7E8 --id 1234 --control freeze

# Tester present
uv run main.py tp --txid 7E0 --rxid 7E8

Available subcommands: session, read, write, reset, routine, io, tp, dtc, clear, security, flash

All hex values accept formats: 7E0, 0x7E0, 01020304, 0x01020304

License

MIT License - see LICENSE for details.