TD
Overview
The Train Describer feed contains message about Train movements at the Signal Berth Level. Messages come in 4 types, all in JSON format:
- CA - Berth Step
- CB - Berth Cancel
- CC - Berth Interpost
- CT - Heartbeat
Messages only exist for trains of headcodes classes, 1, 2 and 9.
Messages
Messages consist of a reference key and then the main JSON string.
The Reference key is the message type followed by _MSG, all in Upper case.
Each message can contain the keys,
- to
- time, in Milliseconds
- area_id, see TD_Areas
- msg_type
- from
- descr, the Train's headcode
- report_time, eg 0842, is 9:42 in the morning,
CA
Contains: to, time, area_id, msg_type, from, descr
Example
{ "CA_MSG": { "to": "0041", "time": "1338289664000", "area_id": "LB", "msg_type": "CA", "from": "0033", "descr": "2T33" } }
CB
Contains: time, area_id, msg_type, from, descr
Example
{ "CB_MSG": { "time": "1338289665000", "area_id": "SK", "msg_type": "CB", "from": "4333", "descr": "1U29" } }
CC
Contains: to, time, area_id, msg_type, descr
Example
{ "CC_MSG": { "to": "FN13", "time": "1338289665000", "area_id": "ZG", "msg_type": "CC", "descr": "1A40" } }
CT
Contains: time, area_id, msg_type, report_time
Example
{ "CT_MSG": { "time": "1338289669000", "area_id": "WJ", "msg_type": "CT", "report_time": "0842" } }