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"
   }
 }