mCoreClock is more precise than SystemFrequency because the variable holds the clock value at which the core is running. Changed startup concept</p>
<p>The old startup concept (calling SystemInit_ExtMemCtl from startup file and calling SystemInit from main) has the weakness that it does not work for controllers which need a already configuerd clock system to configure the external memory controller.</p>
<p>Changed startup concept</p>
<ul>
<li>SystemInit() is called from startup file before premain.</li>
<li