JT/T 808
JT/T 808 Frame Decoder
Decode framing, checksum, header and body boundaries from a JT/T 808 hex frame.
Browse protocol tools
Vehicle telematics protocol tools
Local-first parsers and diagnostics for JT/T 808, 809, 1078, GB/T 28181 and binary network data.
38focused tools
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Local by designYour sample data stays in this browser.
Browse protocol tools
38 tools shownJT/T 808
JT/T 808 Header Decoder
Inspect message ID, body attributes, terminal ID, serial and subpackage fields.
JT/T 808
JT/T 808 Escape & Unescape
Apply or reverse the 7e and 7d byte escaping used inside JT/T 808 frames.
JT/T 808
JT/T 808 0x0200 Location Decoder
Decode alarm, status, coordinates, altitude, speed, direction and BCD time.
JT/T 808
JT/T 808 Vehicle Status Decoder
Inspect ACC, positioning, hemisphere, operation and vehicle-state bits.
JT/T 808
JT/T 808 Terminal ID BCD Converter
Convert terminal digit strings to packed BCD bytes or decode BCD back to digits.
JT/T 808
JT/T 808 0x8001 Response Builder
Build a legacy-header platform general response with checksum and frame escaping.
JT/T 808
JT/T 808 Extra Information TLV Decoder
Split optional location extras into ID, length and value records.
JT/T 808
JT/T 808 TCP Frame Splitter
Extract complete 7e-delimited frames from a concatenated TCP hex stream.
JT/T 809
JT/T 809 Header Decoder
Inspect length, serial, message ID, platform ID, version and encryption fields.
JT/T 809
JT/T 809 Message ID Lookup
Look up common platform login, link, information and positioning message groups.
JT/T 809
JT/T 809 Length Validator
Compare the declared four-byte message length with actual unescaped bytes.
JT/T 809
JT/T 809 Platform ID Converter
Convert the four-byte platform center ID between decimal and big-endian hex.
JT/T 809
JT/T 809 Frame Boundary Finder
Find candidate 5b-to-5d packet boundaries in a concatenated hex stream.
JT/T 1078
JT/T 1078 Packet Header Decoder
Inspect sync marker, sequence, SIM BCD, logical channel and packed data type.
JT/T 1078
RTP Sequence Analyzer
Measure gaps, duplicates and out-of-order transitions in RTP sequence samples.
JT/T 1078
RTP Timestamp Delta Analyzer
Convert adjacent RTP timestamp deltas into milliseconds for a selected clock rate.
JT/T 1078
JT/T 1078 SIM & Channel Key
Build or split a stable stream key from SIM BCD and logical channel.
GB/T 28181
GB/T 28181 SIP Message Parser
Parse request/status lines, headers, identifiers and body boundaries.
GB/T 28181
GB/T 28181 SDP Parser
Inspect origin, connection, media, payload and attribute lines in SDP.
GB/T 28181
GB/T 28181 Device ID Structure Check
Check a 20-digit identifier and display conservative structural segments.
GB/T 28181
GB/T 28181 Catalog XML Inspector
List DeviceID, Name, Status and item counts from a catalog response.
GB/T 28181
GB/T 28181 SSRC Converter
Convert SSRC values between unsigned decimal and eight-digit hexadecimal.
GB/T 28181
GB/T 28181 SIP Flow Checker
Review ordered SIP start lines for registration or media-session gaps.
GB/T 28181
SIP Content-Length Checker
Compare a SIP Content-Length header with UTF-8 body byte length.
Binary & network
Protocol Hex Cleaner
Remove spaces, 0x prefixes and separators, then validate complete bytes.
Binary & network
Binary Byte Offset Slicer
Extract a byte range and show its absolute offsets from a hex message.
Binary & network
Endianness & Integer Converter
Reverse byte order and inspect unsigned big- and little-endian values.
Binary & network
CRC-16 Calculator
Calculate common MODBUS and CCITT-FALSE CRC-16 variants from hex bytes.
Binary & network
Generic 1-Byte TLV Decoder
Split a simple type-length-value byte stream into offset-aware records.
Binary & network
IPv4 & Port Binary Converter
Convert an IPv4 address and port into network-byte-order hex.
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Engineering guides
Diagnose the layer before the field
Detailed workflows for framing, version selection, SIP signaling, RTP media and binary evidence, with safe sample handling and verification boundaries.
JT/T 808 frame diagnostics: boundaries, versions, BCC and location data
Most field-decoding failures begin earlier than the field itself. This guide validates stream boundaries, unescaped bytes, checksum and header layout before interpreting a message body.
Read guideJT/T 809 platform exchange: header, length, identity and stream boundaries
Inter-platform captures fail when transport boundaries, escaping, declared length and peer configuration disagree. This guide establishes a conservative validation sequence.
Read guideJT/T 1078 media diagnostics: packet headers, RTP timing, PS and H.264
A black screen can originate in signaling, transport loss, timestamp handling, PS reconstruction or codec data. This guide isolates each layer in order.
Read guideGB/T 28181 diagnostics: SIP dialogs, SDP media and Catalog XML
A syntactically valid message can still fail at transaction, dialog, profile or media layers. This guide correlates those layers without exposing credentials or real endpoints.
Read guideBinary protocol debugging: normalization, offsets, byte order and checksums
Hex utilities are useful only when the byte boundary and interpretation assumptions are explicit. This guide keeps representation work separate from protocol meaning.
Read guide