* Added a PC-6001 cartridge software list XML, and hooked up to the driver;
* Fixed a regression bug with machine_reset fn where PC-6001mkII was implicitly overriding its memory model when a cart was inserted, causing being stuck at POST;
* Improved irq handling and removed a couple kludges, fixing hangs caused by multiple irqs being fired at the same time;
* Added PC-6601SR "Mr. PC", and improved the specific SR video mode already used by PC-6001mk2SR;
* Refactored PC-6001mkIISR / PC-6601SR memory model to use address_map_device, allowing BIOS booting and .cas loading in mode 6. Replace AY8910 with YM2203;
* Add keyboard inputs F1-F10, and fixed the specific irq vector dispatch;
* Add preliminary FDC internal/external interface. Hooked up PC80S31 to external i/f as a proof of concept;
* Fixed timer enable (fixes Yakyukyo and Punchball Mario boots), and fixed different timer resolution with PC-6001mk2SR so that cursor blinking happens at the right frequency;
New machines marked as NOT_WORKING
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PC-6601SR "Mr. PC" [anonymous]
New NOT_WORKING software list additions
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pc6001_cart.xml: Tutankham [HardcoreHubz, cyberat2600, Gaming Alexandria]
