FAB ETT format

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FAB ETT format is a teletext page file format from F. A Bernhardt GmbH, generated by the the FAB Editing Terminal for Teletext.

The following details are given in the manual of the ETT for Windows Level 2.5 Demo Version.

When teletext pages are stored in FAB ETT file format the files are stored with extension .TTP and contain following data:

Byte 0:           Number of used rows (1 to 49)
Byte 1..42:       Row 0
Byte 1:           SO (0Eh)
Byte 2:	          80h
Byte 3..32:       Page name + odd parity (first 30 bytes, rest starts at position 2060)
Byte 33..35:      80h
Byte 36:          Left Margin (0 to 38) + odd parity
Byte 37:          Right Margin (1 to 39) + odd parity
Byte 38:          Top Margin (1 to 22) + odd parity
Byte 39:          Bottom Margin (2 to 23) + odd parity

Byte 40:          Time for display (3 to 60), bit with value 64 should be set to disable numbering of subpages (FAB System only)+ odd parity

Byte 41:          FAB System only, 
bit 0 (1)         = inhibit header
bit 1 (2)         = C4 for transmission
bit 2 (4)         = out of sequence
bit 3 (8)         = inhibit display
bit 4 (16)        = C5 for transmission
bit 5 (32)        = C6 for transmission
bit 6 (64)        = set to 0
bit 7 (128)       = odd parity
Byte 42:          Character Set + odd parity (0=GB, 4=D, 2=S, 6=I, 1=F, 5=E, 3=CS)

Byte 43..2059:    Data rows (as specified in byte 0 minus 1), each consisting of block of 42 bytes:

Byte 0:	          SO (0Eh)
Byte 1:           Packet (Row) number + odd parity
Byte 2..41:       Contents of data line

Byte 2060..2069:  Page name + odd parity (last 10 bytes)

Remarks:

1. Data lines should be stored in the following order: X/27 (0 or 1 packets),  X/26 (0 to 15 packets),  X/1..X/23 (only lines which contain characters other than 20h), X/24 (0 or 1 packet), X/25 (0 or 1 packet)
2. Data in data lines should be encoded according to teletext specification. For lines X/1 to X/23 use odd parity characters.
3. Unused space at the end of file can be filled up with character 20h.