Why in my Per Tile Sequence Quality plot, the Y-axis starts with 1101?

Question

[ManuelDB]

FastQC (version 0.11.9) ran with Galaxy

Measure Value

Filename Cardiac_R1_fastq

File type Conventional base calls

Encoding Sanger / Illumina 1.9

Total Sequences 5342529

Sequences flagged as poor quality 0

Sequence length 101

%GC 49

Answer 1

[GenoMax]

Illumina has traditionally used those tile numbers back from the days when flowcells were imaged using individual snapshots.

More here: http://seqanswers.com/forums/showthread.php?t=19259

1101 - 1 - Top surface, 1 - First swath, 01 - Tile 01 (photo 01)