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--- base:efficient_tod_initialisation [2019-05-20 11:45] – [Proper solution] silverdr
+++ base:efficient_tod_initialisation [2020-01-31 17:49] – [Proper solution] silverdr
@@ Line 50: / Line 50: @@
   * Short and fast
-Please also note that we use CIA #2 and not CIA #1. CIA #2 is chosen because changing the timer values there does not affect regular IRQ timings. Moreover, KERNAL re-initialises those timers whenever it wants to use them. This saves as a few bytes, which would otherwise be needed to save and restore timer registers' original values. Last and least we do not disable NMIs as it is assumed that checking/setting the params will be done as part of application initialisation, before setting up IRQ/NMI handlers.
+Please also note that we use CIA #2 and not CIA #1. CIA #2 is chosen because it timers are by default not used by the system. Moreover KERNAL initialises those timers according to its needs, whenever it wants to use them. This saves us a few bytes, which would otherwise be needed to preserve original settings. Last and least we do not disable NMIs as it is assumed that checking/setting the params will be done as part of application initialisation, before any IRQ/NMI handlers are set.
 ===== Dual purpose =====
 I mentioned before that this routine can serve also another purpose and give us potentially even more savings. Yes, with addition of only a few bytes: