From: lepton@panix.com (Mike O'Connor)
Newsgroups: comp.sys.newton.misc
Subject: Inside the Newton MP2000 - A Tour
Date: Mon, 21 Apr 1997 18:53:55 -0400

I got a Newton MessagePad 2000! It's great, I LOVE gadgets. I wonder what's
inside it?

Opening the Newton MP2000 is foolish. You will void the warantee. You may
break the device. You may rip a wire. You may break the tabs that hold the
case together. You may lose your data. You may hate yourself if you do it.
DON'T OPEN YOUR NEWTON. DON'T DO IT.

I'm one of those idiots with his head in the clouds. I think I know it all
and can do it all. I was warned. But I opened it - and lived! These
instructions show how I did it, and give you a tour of the inside. If you
do it, don't blame me when even if you follow what I wrote exactly. I
WARNED YOU. DON'T DO IT. Just open the box mentally, it is much safer. Have
I written enough disclaimers? OK.

Make sure you have backed up everything fully. Your internal data is going
to be lost, so make sure you can restore it.

The six sides of the case are:

FRONT = The screen side of the Newton.

BACK = The side of the Newton with the MessagePad 2000 label on it.

TOP = The side of the Newton with the AC and serial port sockets.

BOTTOM = The side, umm, opposite the top.

PC CARD SIDE = The side with the PC card slots.

HINGE SIDE = The side with the screen cover hings and power switch.

Remove any PC cards.

Remove the pen.

Remove the battery pack. After several minutes, the internal
supercapacitor, which keeps enough power for you to change batteries
without losing data, in the Newton will drain and all your internal data
will be gone.

Open the door at the top of the case which covers the AC and serial sockets.

Remove the cover completely by unlatching it at the hinge. By the way,
there is a little peice of plastic right in the carck between the two
halves of the case, near the top of the hinge. This is a little cover for a
slot where a ribbon cable could come out someday, if someone made, for
example, a screen cover which had a built in keybord. This plastic thing is
going to fall out when you open the case.

Make sure you have a soft surface to place the Newton on, you don't want to
scratch the exposed screen while you are working with it screen-down.

Remove the four phillips head screws on the back of the case. No, the case
won't open yet, it is still securely closed.

When we open the case, we will take the bottom half of the case off. The
guts of the Newton are attached to the top and sides of the case and so the
screen, big circuit boards and stuff won't come loose and spray all over
the place. But, some small, important parts WILL come loose when we open,
so we must be careful.

The Newton is held together by plastic tabs and latches. You must be very
careful not to break these. Take a look in the battery compartment, at the
inside bottom edge of the case. You will see three of these latches along
the bottom, one right at the entry of the battery compartment, one in the
middle, and one at the deep end. These latches are all around and are what
are still holding the case together. In each latch, the back half of the
case has a tab with a slot, and the front half of the case has the thing
that hooks into the slot.

By checking out the latch closest to the opening of the battery slot, you
can get a good look at how to gently unhook it. You press in on the back
half of the side of the case, and this frees the tab from the hook so you
can separate that part of the case. But you can't just do this all at once.

The side of the case with the PC card slots will open relatively easily,
but the side of the case with the hinge and power switch is very tightly
held. We must use finesse.

The latch at the bottom of the case near the opening of the battery
compartment unhooks easily, then unhook the one at the center of the bottom
of the case, then the one on the other side. You should be able to get the
bottom of the PC card side open about a quarter inch now, but the hinge
side of the case is still held fast, as is the top of the case.

On the PC card side of the case, there is no latch in the middle, but the
one near the top is very difficult.

Now if you examine the top edge of the case, you can see how it is going to
separate. The AC, serial port and cover are all going to stay with the
front of the case, as will the infrared port. The opening for the pen is
going to come with the bottom of the case. The dark red plastic covering
the infrared port is loose and is going to fall out when the case opens.

With great difficulty, the next thing is to free the latch which is on the
PC card side of the case, 3/8 from the top, very near the infrared port.
You can't push in on the front part of the case under the latch because it
is too solid, so you want to sort of make the top half of the case bulge
out a little, and then pull. This is where you will break some of the
plastic in this latch and regret you ever started this operation. But with
a little frightening force, much carefulness, patience and some luck you
will free this latch with no damage and be able to raise the case about a
half inch or so. The plastic cover for the infrared port will fall out, put
it aside.

Now you can open the whole PC card side of the case about a half inch and
get your first good peek inside. Latches near the pen holder and along the
hinge side of the case still hold the back cover on. Don't pull it too far
open or you'll crack the back cover near the pen holder side of the AC port
cover.

Now, work on the latches in the recessed hinge section of the hinge side of
the case. One latch is 3/4" above the bottom of the hinge section, another
is 1 1/2" below the top of the hinge section. With the cover partly free,
it is a little easier to push on the back part of the case to free these
latches. The corner of the case with the switch and pen holder is still
held fast, so don't lift the case too high or you will crack the back of
the case near where that little slot-cover thing is near the top of the
hinge section. That slot-cover thing is loose and will fall out when the
case opens.

Freeing this last corner is the hardest part. The power switch is secure to
the front half of the case, nothing will fall out there. The pen holder
hole is covered by plastic which is part of the back of the case we are
removing, but the pen holder unit itself is secure to the front of the
case, as is all the circuitry. There are no wires or anything attached to
the back of the case that you have to worry about. You mainly have to worry
about not breaking the plastic case back.

There is a latch on the hinge side, just under the power switch and above
the slot-cover thingie. Once you get that unhooked, there is just one more
latch, which is between the pen holder and the AC cover.

On this last latch, be careful not to lift the cover too high or you will
crack the plastic covering the pen holder hole. However, that is what you
have to do to free the latch. Be careful and extremely patient and all of a
sudden, the cover will come free!

The Newton is open! Take that little plastic slot-cover thing and put it
aside, and now we can take a good look at the unit.

The indise of the back cover is silver. The Newton case is electrically
condictive, and serves as electromagnetic shielding. A thin, clear plastic
sheet is glued to the inside of the cover, to keep the case from shorting
out the circuits below. The cover also has those little plastic hook things
which hold the open screen cover. You can see how they are cleverly made
with tiny plastic springs. There is also the reset button, a little plastic
button that in turn pushes against the real reset switch which is mounted
on the main circuit board.

The main circuit board is fairly tightly packed, but perhaps not as much as
a state of the art cell phone might be. It is, however, filled with a large
number of surface-mount components.

The pen holder tube is a suprisingly solid unit, but if you peek in the
open edge of the tube along the hinge side, you can see the very
interesting latching mechanism which holds the tip of the pen securely.

The infrared module is enclosed in its own shiny metal case. There are two
LEDs to transmit light, and a third to receive.

Down at the battery compartment, which is also a solidly made plastic hunk,
you can see the metal lever which unlatches the battery. Even in an
unopened unit, if you look in the battery compartment, you can see that
when you move the lever to unhook the battery, it moves a latch which is
midway down the battery compartment.

In addition to the two power leads from the battery which make contact at
the deep end of the battery case, you can see that there are two additional
leads that make contact midway along the bottom side of the battery
compartment. If you peek inside the battery compartment you can make them
out. These make contact with extra contacts on the rechargable battery
pack. I believe they lead to a thermistor inside the battery pack itself,
and that the Newton uses the internal temperature of the battery to help
gauge recharging and remaining battery time. I assume there is another
thermistor on the main board itself to gauge the internal temperature of
the Newton to compute an "ambient" temp to compare with the battery temp,
but I didn't spot it. Note I assume this would be the temp of the inside of
the unit, not of the air in the room.

Next to the battery compartment, near its center, on the main circuit
board, is a relatively large wire-wound transformer. I believe that this is
part of a voltage converter which is used to power the backlight. This is
the thing that makes that slight humming noise you hear when the backlight
is turned on.

At the center of the PC side of the circuit board is the super capacitor.
This holds a voltage, so that even when you have removed the battery, the
Newton will not lose its memory for a while. This takes the place of the
backup battery which used to be in older models. [5.5V 0.10F]

There are a number of sockets on the circuit board, and one of them holds a
rather large daughtercard! It is 2.4" by 1.6" with a corner cut out. It has
a substantial edge connector and is easily replacable (once you get the
darn cover off.) It is a 72 pin connector and the board removes and inserts
just like a SIMM or DIMM, with two side latches and you just lift it out.
Only two chips are on this board, on the exposed side. However, the
underside has traces for four more chips! I suspect you could squish ten
chips on this board if you really tried. Board markings: X1036YCZ and
IBI,M4V0 Chips are Sharp dated 9707 marked LHME5BT3 and LHME5BT4.

I don't have my books handy to tell me what any of the chips in the Newton
are, but the date marks mean the year 97 and the week 07 of manufacture.
Thus, these chips were made in mid-Feburary and must have been placed in
the unit hot off the foundry line and shipped to yours truly to get it one
month later.

My guess is that these daughter board chips are ROM containing the
operating system. This would mean that the main ROMs in the Newton 2000 are
easily field replacable. I also assume that this baord could contain quite
a bit of additional RAM or ROM if desired.

In addition to the daughter board socket, there are little wired connectors
for the power switch, infrared, AC. speaker, microphone and battery. A
ribbon cable connector, at the center of the pen-holder edge of the board,
connects to a ribbon cable which goes to the touch screen.

There is also an empty connector toward the top of the board. This tiny
32-pin connector is for an internal modem.

If you look at the top of the case, under the top cover between the pen
holder hole and the AC socket, you will see a square peice of plastic. This
is removable. Behind it is an emply place, about 0.6" deep which is where
an RJ phone jack will go. It looks like you could make a daughterboard
which could be fairly substantial, say 2" by 1.5", that plugged into this
socket and also had the phone jack which would fit into this space.

When opening the case, we notice that there is this little slot in the side
of the case, near the top of the hinge area of the hinge side of the case,
which is covered by a peice of plastic. This could be a slot for a ribbon
cable. My speculation on this is that perhaps the modem connector can also
handle a keyboard. The screen cover could be replaced by a new, perhaps
bigger cover which had an integral keyboard in it, making the Newton into a
clamshell unit.

I was insane enough to open the back of the Newton, but not enough to
remove the circuit board itself to see what is underneath. However, I
believe that there is not very much underneath. Most of the space is taken
up by the PC slots, and of course the screen.

The clock crystal on the board is marked 3.686R7A.

The CPU of the Newton is of course the DIGITAL StrongARM chip. It is dated
A9702 and marked SA-110S DC1035S JD0726.

There are four chips from Cirrus Logic, including the largest one on the
board, marked CL-PS7010-QC-B 73786-699BF 9649 J. Two are marked
CL-PS7030-VC-A 9647 J and the last is marked CL-PS7020-VC-A 9624 J.

Two other chips from Sharp I assume are (DRAM?) memory, marked
LH28F016SUT-10. Two more chips I assume are (flash?) memory have a
manufacturer symbol I don't recognize and are marked 51W4260CLTT7.

Other glue chips include: LTC1323CG; S19712DY T618CB; V573; 2302; 2401; and
MAX1771.

Putting the unit back together is easy. First position the plastic thing
covering the hinge slot, and the one covering the infrared port. Then
carefully position the cover and press it on. The latches snap into place
fairly easily. Set the hinge side of the cover in place first, then hinge
it down, being careful with the top edge and making sure the infrared cover
is ok. Then the bottom and PC card edges. Make sure all the latches are
secure. Replace the four screws. Insert the battery. Say a little prayer
and turn it on. If you have been lucky, the Newton will then start up with
its initial setup procedure. Restore the Newton data and you are all set!

I hope you enjoyed this tour. Permission is granted to redistribute this
article provided it is kept intact.

Mike O'Connor
Leptonic Systems Inc.
lepton@panix.com


REPLY:

From: lepton@panix.com (Mike O'Connor)
Newsgroups: comp.sys.newton.misc
Subject: Re: Inside the Newton MP2000 - A Tour
Date: Mon, 21 Apr 1997 21:21:18 -0400

A techie-type person told me a little more about the circuits in the unit:

> At the center of the PC side of the circuit board is the super capacitor.

The capacitor will last for many minutes, and that it is probably a 1F
size, not 0.1F. That's super!

> There is also an empty connector toward the top of the board. This tiny
> 32-pin connector is for an internal modem.

The 32-pin connector has all the serial and general purpose ports, power
and grounds on it. Sounds like you can connect almost anything to it...

> There are four chips from Cirrus Logic, including the largest one on the
> board, marked CL-PS7010-QC-B 73786-699BF 9649 J. Two are marked
> CL-PS7030-VC-A 9647 J and the last is marked CL-PS7020-VC-A 9624 J.

The two identical chips are the PC card controllers. Another other is the
serial interface chip that handles the modem, keyboard, IR and general
purpose ports.

> Two other chips from Sharp I assume are (DRAM?) memory, marked
> LH28F016SUT-10. Two more chips I assume are (flash?) memory have a
> manufacturer symbol I don't recognize and are marked 51W4260CLTT7.

Seems I had this backward, the 28F016 chips are 4M flash memory. The 4260
chips are 1M DRAM, 256K x 16. I didn't notice the extra pads under the DRAM
chips. I wonder what would happen if I unsoldered the 1M DRAM chips and,
using the unused pads, soldered in some Hitachi HM51W16160 or Motorola
MCM516165BV 1M x 16 DRAM chips? That would be four times as big...

> LTC1323CG
This is the AppleTalk chip.

> MAX1771
This is the voltage converter chip for the backlight.