KDE PIM/KItinerary/Trenitalia Barcode: Difference between revisions

Revision as of 09:20, 11 May 2019

always 67 bytes
exactly for one passenger/leg
does not seem to contain signatures, checksums or compression, based on minimal bit pattern changes on adjacent tickets
a lot less null bytes when PNR/seat reservation are present (ie. highspeed train tickets?)
there is a unique, globally sequential ticket number, 2017 in the 600M range, 2019 in the 1B range, which suggests 32bit might be a bit short for this

Byte:Bit (MSB)	Content	Meaning	Notes
0:0 - 4:7	0x20 0x14 0xC2 0x08 0x10	header?	fixed value in all samples
5:0 - 7:7		date?	varies between samples
8:0 - 12:7	null
13:0 - 14:3	0000 0100 0000		fixed values in all samples
14:4 - 17:3	24 bit uint	UIC station code of departure
17:4 - 18:2
18:3 - 21:2	24 bit uint	UIC station code of arrival
21:3 - 22:3
22:3 - 24:2	16 bit uint	train number	could be as little as 14 bits too
24:3 - 29:7	null
30:0 - 38:7			null if no PNR present, seems to contain seat number?
39:0 -42:7	null
40:0 - 50:7			null if no PNR present, unknown content otherwise
51:0 - 57:7	0x0B 0x65 0x23 0x18 0x40 0xE6 0xC0		fixed in all samples?
58:0 - 58:3	null		might be part of the ticket number?
58:4 - 62:3	32 bit uint	ticket number
63:4 - 65:7	null
66:0 - 66:7			varies between samples

there is one sample where the departure and arrival UIC station codes are equal, contrary to what's in the corresponding PDF
for international destinations the station code does not actually seem to be a valid UIC station code, but there is only one sample to back this up so far

@@ Line 26: / Line 26: @@
 | 18:3 - 21:2 || 24 bit uint || UIC station code of arrival ||
 |-
-| || xx bit uint || train number ||
+| 21:3 - 22:3 || || ||
 |-
-| 25:0 - 29:7 || null || ||
+| 22:3 - 24:2 || 16 bit uint || train number || could be as little as 14 bits too
+|-
+| 24:3 - 29:7 || null || ||
 |-
 | 30:0 - 38:7 || || || null if no PNR present, seems to contain seat number?