Re: Apple II Minus Question

[mjmahon@aol.com (Michael J. Mahon)]

Bryan Parkoff replied (to me >>):

>> A ][+ (please, there is no such thing as a "minus"), once
>> stopped displaying color because the crystal went out of
>> spec.
>    It is OKAY for me to say "Apple II Minus" or "Original Apple II".  It is
>not really Apple II Plus.  I do understand that there is no such label that
>says "Apple II Minus".  It always says "Apple II"  It helps us to recognize
>"Apple II Minus" and "Apple II Plus" rather than "Apple II" and "Apple II
>Plus".

The reason for nomenclature is clear communication.  Making up
new names for old things is not generally a good idea.  I know
what you mean, but "Apple II" already carries that meaning.

>> As you have observed, the Apple ][ does not have a hardware
>> reset (unless a Disk ][ controller is present), and must be
>> manually reset to get into the monitor.
>    Can you explain, "Apple II Minus does not have RESET hardware?"  Do you
>mean that 6502 CPU does have RESET built in, but Apple II's keyboard has
>RESET key while it is not WIRED to 6502 CPU?  It is why RESET key is not
>working that is never hooked up to 6502 CPU.  Does it mean that everyone
>owns Apple II Minus must always turn off and on power every time to reboot
>Apple II Minus?

I should have said the original Apple II doesn't have a _power on_ RESET.
The RESET key works just as on any other Apple.

What it means is that the original Apple II is not in a well-defined
state when you turn it on.  You must manually press RESET to
put it in a well-defined state.

When the Disk ][ Controller was designed, it incorporated a power on
RESET circuit which resets an original Apple II at power on--and
automatically boots a disk if the Autostart ROM is installed.

>    I turned on Apple II Minus before HGR is turned on with both 12 black
>and white horizontal lines in the screen.  No assembly prompt, Integer /
>AppleSoft BASIC prompts are shown.  I tried to hold and press CTRL-B keys to
>return to Integer BASIC from Old Monitor Routines, but nothing is working.

You must first press RESET.

>    Is it true that AutoStart Monitor Routine and Old Monitor Routine zeroes
>"FF FF FF FF" in each even page and "00 00 00 00" in each old page?  Or...Is
>it the way how RAM chip zeroes "FF FF FF FF" and "00 00 00 00" in both
>even/odd pages before power is turned on?  It is impossible to show garbage
>characters in each RAM chips.  On unenhanced Apple //e has "FF FF FF FF" and
>"00 00 00 00" in both even/odd pages, but it NEVER has any garbage
>characters unlike Apple II does.  I don't know if it is true that it is done
>to zK¢by neither RAM chip or Monitor Routines.

No, those are just the power-up states of the DRAM chips.
-michael

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