apple/apple2e.cpp: Correctly reset IOU softswitches on system reset

[xotmatrix]

Some IOU softswitches are not being reset when the system is reset. This can leave the display and annunciators in an incorrect state after a reset.

From a fresh start, enter the following into the monitor to enable 80-column video and then press RESET. Note the 80-column video remains enabled which is not correct.

*C00D:1

From a fresh start, enter the following into the monitor to draw MouseText characters to the screen and then press RESET. Note the MouseText characters remain enabled which is not correct.

*C00F:1 N 428:40 41 42 43 44 45

This patch corrects these issues by adding reset handling for the missing IOU softswitches:

• 80COL
• ALTCHR
• AN0
• AN1
• AN2
• AN3

In addition, reset code related to MMU, IOU, and LC softswitches has been reorganized into logical groups.

[rb6502]

I think we have enough duplicated code now to break a lot of this out into a class member function and just call it from both the keyboard reset and machine_reset().

[xotmatrix]

I'm all for a single reset routine. People have grown impatient with me for not accepting that they perform different tasks on some philosophical level.

That said, some care should be given to m_romswitch and possibly other flip-flops that do not change on a hardware reset and start in an unknown state.

[rb6502]

It's not philosophical so much as a MAME architectural thing.

machine_reset() is intended to be a power-on everything-gets-hit reset, and there isn't a native concept of something like Control-Reset where only some components know about it. The reset everything machine_reset() style is totally reasonable for all the stuff MAME emulates where it has no reset switch (arcades, synthesizers, some consoles/handhelds) but you still would like to be able to reset it. The A2 obviously isn't that.

There's a lot of overlap so we definitely want both cases calling a common routine, but they can't be 100% identical since machine_reset() should put things like ROMSWITCH into a reasonable known state that a Control-Reset doesn't touch. That's obviously a much longer list on the II/II Plus than the IIe/IIc, so hopefully for the IIe/IIc we can have most of what both paths do in the common routine.