An activation message is produced when a train entity is created from a schedule entity by the TRUST system. The train entity refers to a single run of a train on a specific day whereas the schedule entity is potentially valid for several months at a time. Within TRUST, this process is known as 'Train Call'. Most trains are called automatically (auto-call) before the train is due to run, and there is no specific business event which triggers the call. The exception to this is for schedules which are "Runs as required", or "Runs to terminals/yards as required" (flagged with Q or Y in the schedule.) By default, it is assumed that the train will not run unless the train operator decides that it will; the train operator will submit a message to the TRUST system and this will then cause the schedule to be activated for that day. This process is known as 'manual call'.

Train activations are usually received 1 - 2 hours before the train is due to run, but these trains may be manually called earlier if some details of the train are due to change.

The activation message includes the schedule UID, schedule STP Indicator, and a 10-character ID (unique only within a calendar month) which is seen in all further message for a the train.

Data structure

Header

Field	Description
msg_type	'0001' for an activation message
source_dev_id	Always blank for an activation message
source_system_id	"TRUST" for an activation message
original_data_source	"TSIA" for an activation message

Body

Field	Description
train_id	The 10-character unique identity for this train (used in other TRUST message types)
creation_timestamp	The timestamp, in milliseconds, when the train was originally created in TRUST
tp_origin_timestamp	The date, in YYYY-MM-DD format, the train runs. For trains activated before midnight that run after midnight, this date will be tomorrow's date. Note: there is currently a problem with the tp_origin_timestamp field due to the truncation of the timestamp. This only occurs during daylight savings for trains which start their journey between 0001 and 0200 the next day. To work around this problem, use the date in the origin_dep_timestamp field.
train_uid	The UID of the schedule being activated - either a letter and five numbers, or a space and five numbers for VSTP trains
sched_origin_stanox	STANOX of the originating location in the schedule.
schedule_start_date	The start date of the schedule
schedule_end_date	The end date of the schedule
schedule_source	Set to 'C' for schedules from CIF/ITPS, or 'V' for schedules from VSTP/TOPS
schedule_type	Either C (Cancellation), N (New STP), O (STP Overlay) or P (WTT/LTP)
schedule_wtt_id	The headcode and TSPEED of the train (either '1', '2', '3', '4', 'C', 'M', 'N' or 'O')
d1266_record_number	Either '00000' for a CIF/ITPS schedule, or the TOPS unique ID of the schedule
tp_origin_stanox	If the train is due to start from a location other than the origin (i.e. it is part-cancelled), the STANOX of the location at which the train starts, otherwise the STANOX of the scheduled origin location. If this field is populated, it will be typically be in response to a VAR issued through VSTP or SCHEDULE.
origin_dep_timestamp	The estimated WTT time of departure from the originating location
train_call_type	Either 'AUTOMATIC' for auto-called trains, or 'MANUAL' for manual-called trains
train_call_mode	Set to 'NORMAL' for a train called normally, or 'OVERNIGHT' if the train is called as part of an overnight batch process to activate peak period trains early
toc_id	Operating company ID as per TOC Codes
train_service_code	Train service code as per schedule
train_file_address	The TOPS train file address, if applicable