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Elite on the BBC Micro and NES

Version analysis of TWOS2

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

Code variations between these versions are shown below.

Name: TWOS2 Type: Variable Category: Drawing pixels Summary: Ready-made double-pixel character row bytes for mode 4 Deep dive: Drawing monochrome pixels in mode 4

Code variation 1 of 2A variation in the comments only

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Ready-made bytes for plotting two-pixel dashes in mode 4 (the top part of the split screen). See the PIXEL routine for details.
This table is not used by the 6502 Second Processor version of Elite. Instead, the TWOS2 table in the I/O processor code is used, which contains double-pixel character row bytes for the mode 1 screen.
.TWOS2

Code variation 2 of 2Related to the screen mode

Tap on a block to expand it, and tap it again to revert.

EQUB %11000000 EQUB %01100000 EQUB %00110000 EQUB %00011000 EQUB %00001100 EQUB %00000110 EQUB %00000011 EQUB %00000011
EQUB %11000000 EQUB %11000000 EQUB %01100000 EQUB %00110000 EQUB %00011000 EQUB %00001100 EQUB %00000110 EQUB %00000011