Download Washington Apple Pi Journal, May 1985

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The ads said "•.• time-stamp your files ..... ; well,
yes and no. r.t first I used the SOS 'set date-and­
time' command in Apple Writer III, or in the utilities
Device Handling menu of routines to set today's date
and current time, but I never relished going back
every so often to increment the hours. Later, I dis­
covered the unheralded "TimeSet" module in Business
Basic, which made it a lot easier to reset the system
clock without having to retype the date every time.
But it really never was a fully satisfactory arrange­
ment for a sophisticated machine. Like most of us, I
kept waiting for the promised clock with battery
backup - you know that one by heart: "If you need
help, ask your dealer."
Then I stumbled on the November 1982 issue of Softalk
magazine where I found the article, "It's III o'Clock
and All's Well" by Apple III expert John Jeppson.
What follows is nothing original, other than the good
news that the clock chip works extremely well, plus a
few more details to encourage the electronically timid
like myself.
All you need, I learned from Or.
Jeppson, is a timer chip and (he didn't mention that
one) the guts to open the Ill's underbelly.
The
mounting socket for the chip not only is present and
labeled
on
the motherboard, the
circuits
are
completely pre-wired, and the software calls already
are (unbeknownst to owners) installed in SOS.KERNEL.
In other words, once you slip the timer chip in its
socket you are finished - your clock starts ticking as
soon as the power is turned on. The procedure turned
out to be simpler and quicker than antiCipated.
First, you need to buy the clock chip, model\MM-58167\
(or MM-58167A), which you may be able to locate in an
electronic parts store. To save time, I ordered mine
by phone and charged the purchase. Without recommend­
ing one supplier over another, I found Do-Kay Computer
Products in Santa Clara (800/848-8008 in California)
helpful and fast. The price of the chip is less than
ten dollars - 4 mere $8.90 (plus $0.58 tax in Calif­
ornia).
Add $?OO UPS shipping if you don't want to
pick it up. (Speaking of ·picking it up·, be very
careful handl ing the ch ip as stat ic electricity can
ruin it in a flash.) Alternately, a ·Clock III Kit"
with parts and instructions can be purchased for
$60.00,plus $2.00 shipping, from Apex Information
Systems (415/885-1633) in San FrancisCO, according to
the September 1982 'Gazette'.
Now the scary part: exploratory surgery on your baby.
First, flip off the Apple III power switch on the rear
panel.
Then unplug everything from the rear panel
(including the power cord, just to be sure - Ed. Note:
some folks suggest leaving the power cord plugged in
to bleed off any residual charge) because you are
going to turn the machine over; belly up. With the
four rubber feet facing up, orient the Apple III so
that the (upside down) rear panel points away from you
and the keyboard (keys down) fronts you. If you can
find something the right height, prop it under the
keyboard so as to stabil ize the mach ine and keep it
from rocking while you work on it.
Covering the bottom of the Apple III are two rectangu­
lar metal plates extending from front to rear, one
large, one small. The large metal plate covers about
three-fourths of the bottom 1 contains a row of vent
holes over (actually under) the keyboard, and has
affixed a large red sticker with the serial number.
The sticker has a prominent white arrow pOinting to
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the adjoining smaller shiny rectangular plate, with the warning never to remove it as it holds the power supply.
1I0t to worry, we want to remove the large metal plate because, attached on the reverse side, is the Apple's motherboard. To get to it, unscrew the 11 (eleven) small Phillips head machine bolts that secure the cover with attached motherboard to the Apple's
frame. Now gently nudge the cover plate assemb ly away
from the frame, lifting at the small notch cut into the edge of the plate where it adjoins the power sup­
ply cover, using the opposite long edge of the rec­
tangular cover plate as a hinge. '"
As you gently rotate the plate on its long outer edge a few inches, a taut grey cable soon limits your free­
dom to expose more of the board; we have to unplug
that cable. This low-voltage power supply cable (con­
taining ten multi-colored wires) terminates in an opaque plastic 10-pin female plug with a black plastic cover.
The plug mates to a male connector, clearly
labeled POWER in the G-row, fixed to the motherboard. The female plug slides off very easily!
Once the power cab Ie is unplugged, you can fl ip over the motherboard on its back cover to get at the components
being careful not to stretch, bend or press on sane
of the other longer cables you'll see in the far cor­
ners.
If the two-wire black speaker cable gets in
your way, unplug its small ivory terminal connector;
but do mark the socket for, being small, it is hard to
find back. While getting some elbow-room, you'll see
a myriad spider-like IC's, resistors and other elec­
tronic parts on the motherboard.
("
Now that the board rests without stretching any
cables, note that each socket on the board is labeled in white ink with its contents. Moreover, the board is organized in sections with horizontal capital let­
ters along the left side, and numbers along the short side faCing you, so as to help you localize a specific area of the board; for instance intersection G-1 for the power cable receiver plug. Try to identify the area B-3 near the left lower corner. If you can't find it, no worry, inspect the left lower corner of the board till you spot an empty black rectangular
chip holder socket with two rows of 12 small holes. It is the second socket from the long left edge of the board, just one row above the several resistors, capaCitors and small chips on the short edge facing you; about midway between that edge and the "two-
story' memory tower assembly in a 256K Apple III. Surprise!
The empty clock chip holder is clearly
labeled with "58167". Having located the empty socket for the MM-58167 chip,
the rest is easy. The only mistake you can possibly
make is to reverse the chip in the holder. Align the
lettering on the top of your chip the same direction
as its neighbors; probably with the top of the letters
faCing to your left. A second check is to face the
small half-circle notch in one of the two short sides
of the roof of the chip the same direction as the
other chips in the B-row; probably facing you.
(Ed.
It is
Note: Lettering may not always be the same.
more important to perform the second check.)
Now,
very gingerly, place the ch ip with prongs down into
"
the holder so that everyone of the 24 prongs slides
into the corresponding socket contact without bending.
Once again, read the instructions accompanying the
chip regarding static electricity precautions.
When positioned lightly in the socket, and without bending or forCing, nudge the chip in evenly and steadily till contd.
Hay 1985
Washington Apple Pi