Re: Help me ID cards in my Apple ][

[dempson@swell.actrix.gen.nz (David Empson)]

In article <2e3kac$ghd@TAMUTS.TAMU.EDU>
jdb8042@TAMUTS.TAMU.EDU (John Donald Baker) writes:
> In article <2e1amqINNan9@charnel.ecst.csuchico.edu>,
> Don Littlefield II <unibrow@ecst.csuchico.edu> wrote:
>
> >Also it has a 16k expansion card with a switch on it. What is the switch for.
> 
> Ah!  This appears to be the old Apple Language System card.  With the switch
> in one position, you boot up in BASIC (Integer, I think) and in the other
> position, you should start up in Apple PASCAL v1.0 (in the ROM on the card).

Time to clear up the confusion about this switch.  I don't recall
seeing it described correctly yet!

There are two cards I'm aware of which use a switch like this.

The first is a ROM card, which can either contain Applesoft or Integer
BASIC ROMs.  It is intended to go in slot 0 of an Apple II or Apple
II+.  With the switch in the DOWN position, a Control Reset will
select the motherboard ROM, and the monitor on the motherboard will get
control.

With the switch in the UP position, a Control Reset will select the
card ROM, and the monitor on the card will get control.

In its original configuration, the card contained the Autostart ROM
and Applesoft BASIC, and was used in an Apple II (Integer BASIC and
original Monitor ROM on the motherboard).

In its revised configuration, the card contained the old Monitor ROM
and Integer BASIC, and was used in an Apple II+ or upgraded Apple II
(Applesoft BASIC and Autostart ROM on the motherboard).

The old Monitor ROM drops you into the monitor when you press Control
Reset.

The Autostart ROM will do a cold or warm reset, depending on the
contents of some low memory locations.  Without DOS, control would be
passed to the copy of BASIC in the same set of ROMs as the monitor.
If DOS is present, it will restore control to the most recently
selected version of BASIC (using the INT or FP command).


The second card is the one that I think the original poster has.  It is
a 16k RAM card which is supposed to go in slot 0 of an Apple II or
Apple II+.  The card should also have a 2k ROM on it, which contains
the Autostart monitor.

The switch works just like the ROM card - DOWN = reset via motherboard
monitor, UP = reset via card monitor.

The switch should probably be left in the down position, unless you
have an Apple II with the old Monitor ROM and have loaded Applesoft
BASIC into the card.  In this case, putting the switch UP will allow
Control Reset to do a warm start and return you to BASIC.

The switch must be left in the DOWN position if you are using ProDOS
or Pascal, since these operating systems use the entire 16k RAM area,
and the last 2k is used by the ROM if the switch is up.


There is a third possibility, which I haven't seen: a RAM-only card
with a switch.  My guess is that the switch would still work the same
way: it determines whether the language card is activated when you
press Control Reset.

Apple's original language card didn't include such a switch - if you
pressed Control Reset, the language card remained in its current
state.  If the language card was active, the operating system in the
langauge card would get control.  (This is not the case on the IIe and
later machines - the built-in language card is always deactivated when
you press Control Reset.)

There may have been a later card from Apple or a third-party
which provides a switch to select the destination for a reset, but
I've never heard of one.
-- 
David Empson                                                               
dempson@swell.actrix.gen.nz                                                
Snail mail: P.O. Box 27-103, Wellington, New Zealand