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Elite on the BBC Micro

Version analysis of TWFL

This code appears in the following versions (click to see it in the source code):

Code variations between these versions are shown below.

Name: TWFL Type: Variable Category: Drawing lines Summary: Ready-made character rows for the left end of a horizontal line in mode 4

Code variation 1 of 1A variation in the comments only

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Cassette, Flight, Docked

6502SP

Ready-made bytes for plotting horizontal line end caps in mode 4 (the top part of the split screen). This table provides a byte with pixels at the left end, which is used for the right end of the line. See the HLOIN routine for details.
This table is not used by the 6502 Second Processor version of Elite. Instead, the TWFL table in the I/O processor code is used, which contains ready-made bytes for plotting horizontal line end caps in mode 1 (the top part of the split screen).
.TWFL EQUB %10000000 EQUB %11000000 EQUB %11100000 EQUB %11110000 EQUB %11111000 EQUB %11111100 EQUB %11111110
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