Re: Apple II Minus Question

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

Bryan Parkoff replied:

>> >    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.
>    Are you saying that I press and hold Reset key before turn on Apple II's
>power supply?

No, I'm saying that after you turn on the power, you must manually
reset the machine before pressing crtl-B <return>.  (Depending on the
keyboard type/setting, this may mean simply pressing the RESET key
or holding Ctrl and pressing the RESET key.)

>> >    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.
>    So you say that DRAM chips zero "FF FF FF FF" and "00 00 00 00" in both
>even/odd pages?

Yes.

The Apple Monitor routines _never_ touched memory except incidentally
(some zero page locations and the text screen) until the //e, which tromps
on a couple of bytes per page on a reset to make capturing single-load
games more difficult.  ;-)
-michael

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