[sebhc] Emulator Enhancements

[Steven Parker]

Is everyone enjoying this?  Or should Mark and I take it offline?

>1) defining a new UART. Duplicated almost all the code/places that
>the existing ' m_ConsoleUART' class has.
>Result -> I get output that has dropped many characters. I can still
>....it appears the computer is writing
>the next charater before the UART sends out the first one.

Well, getting anything is a good sign.  :-)  But you'll need different code 
to simulate the 8251 of the H8-5.  The 8250's currently being simulated for 
console I/O have different status values and initialization sequences.  The 
tape uses an 8251 also, so looking at how that's handled might help, 
although it will be different enough that it can't just be copied.

>2) Using the existing UART. I.e. mapping the addresses 372 ->350
>and 373 -> 351.
>Result: ...now is showing dropped characters like above.

Same problem: simulating the wrong type of chip.  No telling what states are 
being unintentionally set up in the emulator by the tape s/w sending it 
setup params for a 8251.  Although the emulator could certainly be 
"hardened" a bit so it could withstand simulated port abuse without itself 
crashing.

>If the original ConsoleUART or my new 'CassConsoleUART' is
>initialized for a interrupt:...
>They both will cause the emulator to just beep and not respond to any
>other inputs.

Well, you certainly don't want to enable interrupts unless there's a 
functional interrupt service routine already installed.  :-)  Do we even 
know that this software uses interrupts?  Maybe it just polls the port.

>I'll try some other combinations and see if I can get any more hints by
>using the Logic Analyzer.

Oh yea?  How do you use a logic analyzer on simulated virtual hardware?  :-)

Cheers,

- Steven

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