C) Apple1 ROMcard
( After
revision and correction! )
This card is
corrected, but the size must be optimized later - before passing
the data to
PCB manufacturer - the card must become 2 cm less high and at
least 2 or 3 cm less long !
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.
Please recognize: The scans below from the testing
cards differ from those, that will be ordered from customers in several
points:
1. The slotpadcontacts on the testingboards are NOT goldplated.
The cards ordered by customers will be goldplated
!
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 )
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.
