<story><title>Apple II graphics: More than you wanted to know</title><url>https://nicole.express/2024/phasing-in-and-out-of-existence.html</url></story><parent_chain></parent_chain><comment><author>thought_alarm</author><text>&amp;gt; &lt;i&gt;&amp;quot;Randomly reading from various memory addresses might give the modern programmer some concern about security holes, maybe somehow reading leftover data on the bus an application shouldn&amp;#x27;t be able to see. On the Apple II, there is no protected memory at all though, so don&amp;#x27;t worry about it!&amp;quot;&lt;/i&gt;&lt;p&gt;Funnily enough, protected memory (sort of) arrived with the Apple III a couple of years later in 1980 and it was met with complete disdain from the developer community (&amp;quot;Stop trying to control my life, Apple!&amp;quot;).&lt;p&gt;Apple III ROM, hardware, and kernel memory wasn&amp;#x27;t meant to be directly accessible from the application&amp;#x27;s address space.  The purpose was to increase system stability and to provide a backward-compatible path for future hardware upgrades, but most users and developers didn&amp;#x27;t see the point and found ways around the restrictions.&lt;p&gt;Later, more-successful systems used a kinder, gentler approach (please use the provided firmware&amp;#x2F;bios interfaces please).</text></comment>
<story><title>Apple II graphics: More than you wanted to know</title><url>https://nicole.express/2024/phasing-in-and-out-of-existence.html</url></story><parent_chain></parent_chain><comment><author>PaulHoule</author><text>The first generation of home computers used discrete components for the display controller which is crazy expensive because you need lots of counters, comparators, wide data paths, etc which adds up to a lot of parts.&lt;p&gt;Second generation machines line the VIC-20 and TRS-80 Color Computer used ASICs for the display controller.  Apple though the ][ was on borrowed time and has no idea how long it would last so they were slow to come out with the ][e which was cost-reduced.</text></comment>