Related: <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=10874127" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=10874127</a><p><i>VRAM is also where many &quot;online&quot; development suites—the BASICs and Pascals of the time—expected you to write exception traces. Rather than trying to &quot;break into&quot; a debugger (i.e. cram a debugger into the same address space as your software), you&#x27;d simply have your trap-handler persist the stack-trace to VRAM, switch your tape drive over to the devtools disk, and reboot. The &quot;monitor&quot; would load, notice that there&#x27;s a stack-trace in VRAM, parse it, read the pages it mentions from your program (now on the slave tape) and display them.</i>