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Elite on the BBC Micro and NES

Version analysis of PL21

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

Code variations between these versions are shown below.

Name: PL21 Type: Subroutine Category: Drawing planets

Code variation 1 of 2A variation in the comments only

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Summary: Return from a planet/sun-drawing routine with a failure flag
Summary: Return from a planet-drawing routine with a failure flag

Code variation 2 of 2A variation in the comments only

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

Set the C flag and return from the subroutine. This is used to return from a planet- or sun-drawing routine with the C flag indicating an overflow in the calculation.
Set the C flag and return from the subroutine. This is used to return from a planet-drawing routine with the C flag indicating an overflow in the calculation.
.PL21 SEC \ Set the C flag to indicate an overflow RTS \ Return from the subroutine