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Elite on the BBC Micro and NES

Universe: TT20

[6502 Second Processor version]

Name: TT20 [Show more] Type: Subroutine Category: Universe Summary: Twist the selected system's seeds four times Deep dive: Twisting the system seeds Galaxy and system seeds
Context: See this subroutine in context in the source code References: This subroutine is called as follows: * HME2 calls TT20 * TT111 calls TT20 * TT22 calls TT20 * TT23 calls TT20

Twist the three 16-bit seeds in QQ15 (selected system) four times, to generate the next system.
.TT20 JSR P%+3 \ This line calls the line below as a subroutine, which \ does two twists before returning here, and then we \ fall through to the line below for another two \ twists, so the net effect of these two consecutive \ JSR calls is four twists, not counting the ones \ inside your head as you try to follow this process JSR P%+3 \ This line calls TT54 as a subroutine to do a twist, \ and then falls through into TT54 to do another twist \ before returning from the subroutine