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Apple1 ROMcard |
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Page
No.:A16 |
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Just right from the beginning i knew that i would develop a
ROMcard as alternate storage that will permit to load
resident basic from Eprom instead
from loading it each time from tape. Eprom is more reliable
than tape and faster too. And such an Epromcard would permit
to create a kind of
"Utility Eprom" that contains an editor and a dissassembler
as well as a assembler program or compiler or a diagnostic
Eprom or just some
resident games.
This Card is designed for different kinds of usage: as ROM
Card for 2708 or 2716 or 2732 Eproms - but also for use with
6116 Static RAM.
If the 6116 is used, the user may use a
"backup-accumulator" on board as battery to keep the content
of the static RAM nonviolatile for a
couple of days.
That feature is switched "on"
or "off" by a slideswitch on
top of the card.
This will enable the user to first use the Card with static
RAM for development of the software, that is determined to
be used in the Eprom.
Then - after that software has been tested - the card can
be used with Eproms.
The design of the card contains microswitches and permits
the adressrange of each socket to be chosen with four
4pol-DIL-microswitches
- so each Eprom may use its own selected adressrange.
Each socket permits to be free selectable with either 2708
/ 2716/2732 or 6116 by a socket configuration plug.
I have also integrated the ability to
program the Eproms with integrated ability to produce
the needed programmingvoltage on the card.
The needed programmingvoltage can be switched "on"
or "off" by Jumper at JP1 - and
if it is switched on - it will be controlled by software
on the line"T" and the Read/Write-signal. The
programmingvoltage of 12,5 Volt, 21 Volt, 25 Volt or 26 Volt
will be selected by a jumper at JP2.
The +12 Volt and -12 Volt regulation is integrated too.
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new
layout with far less hight and much better balance
by placing the the accumulator above the slot |
former Layout ( too high )
with less good layout ( bad balance due to outside
placement of accumulator ) |
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due to european laws
and german court decision:
I hereby declare no responsibility to any "deep links"
resulting from the links in this page. I have no influence
to the pages linked hereby in this page and the
contents in those pages. I therefor canīt take any kind of
responsibility to contents in the pages, where these links
direct the readers browser to nor to the
contents resulting from following up links from those
pages. The reference to contents by this links is dependent
ro the status of the date when the links have
been set ( April 2013 ) and it might occur that references
and contents may change by the fact that domains may have
been discontinued from their former owners.
In such cases i canīt take any kind of responsibility to
the changed contents. this is specialy valid to banners,
advertisements or merchandising links in the targeted
pages.
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