Introduction

In the late 1990s, Mitsubishi had a fairly unknown line of portable computers called the Amity (stylized as AMiTY). It included machines in several form factors: the Amity CP/VP was an early form of Tablet PC, with an active WACOM tablet digitizer on the screen, but there was also an even more unusual subnotebook: The Amity CN.

Amity CN

Subnotebooks themselves weren’t unusual for the time (see IBM ThinkPad 500, Chandra, and many other articles on this site), but this one was far smaller than most. Measuring in at 9 x 6.5 x 1.25 inches (22 x 16.5 x 3.2 cm) and weighing only 2 lb 9.6 oz (1180 g) with the Lithium-Ion battery pack installed, this machine was even more lightweight than most other “ultraportables” of the era.

(Amity CN on left, Compaq Contura Aero on right – and the Aero was considered small!)

The Amity CN runs a fanless Pentium 1 at 133 MHz by default (with generous configuration options for processor speed, and other power-saving factors, in the BIOS Setup). 16 MB of memory is built-in, but you can expand this via a single low-profile SODIMM slot under the keyboard. I expanded mine to 48 MB with a 32 MB stick; although my Amity CP from the same era accepted a 128 MB stick, I wasn’t able to get this to work on the CN. Mine was manufactured in 1997 according to the date codes on the ICs inside of the unit.

For power, there is a 10.8V 1350mAh Lithium Ion battery. This appears to be a custom-made battery pack, in the shape of an elongated “D”, and it perfectly fits within the battery compartment (which screws onto the base of the machine). The battery connects with two probe-style terminals, something I’ve never seen on a laptop.

The screen is a glossy, color, passive-matrix LCD (an extremely rare combination!) running at 640×480. It’s bright enough and crisp enough, but it’s not active-matrix, so any movement causes fairly severe motion blur. Combine that with the fast processor, and you can play DOOM at perfect frame rates with a lot of motion blur, also an unusual combination as by the end of the 1990s, most laptop screens were active-matrix.

For sound, the Amity CN has an ESS ES1878 AudioDrive built-in. It does have an internal speaker, but it’s monaural.

On the left of the machine, you will find the headphone and microphone jacks, along with the power button. On the right are two PCMCIA non-CardBus (PC Card) slots. On the rear, there is an infrared blaster/receiver, along with a PS/2 combination port (labeled for both Mouse and Keyboard) the traditional Serial/Parallel/Video and DC Input jacks. It’s worth mentioning that the access door for the Serial/Parallel/Video ports flips 180 degrees, allowing you to use it as a “foot” to prop up the entire machine at a slight angle! This is neat, but nowhere near as over-engineered as the plastic pieces on the Amity CP (see below).

Amity CP

The Amity CP is slightly less portable than its CN relative. While the weight is similar to the CN (with both batteries and hard drive: 2 lbs 13.75 oz, or 1300 g), it’s a tad larger. It’s closer to the size of a traditional (non-ultraportable) notebook of the era: 10 x 7 x 1.5 inches (25.5 x 17.75 x 3.8 cm).

There are several pieces of movable plastic on the rear of the machine’s case that, when combined with the screen lid (which flips open, up and around to the back of the machine) allow you to operate the machine at several angles of incline (vs lying flat):

• A small rectangular piece near the top folds downward, and a smaller piece extends rightward out of that piece. The smaller piece then latches into a recess in the case (not very reclined).
• A very large rectangular piece taking up most of the rear folds downward (reclined), and you can optionally pull a long plastic piece out of that (very reclined).

Here are some pictures of what I’m talking about:

My Amity CP (manufactured in 1999 according to the ICs inside of the unit) has a 200 MHz processor, although the official spec sheet shows (archive.org) that it originally came with 166 MHz. The spec sheet also claims a maximum of 96 MB of RAM, but I was able to run mine with 160 MB by using a single 128MB SODIMM.

For power, it uses two “D”-shaped elongated Lithium Ion battery packs, each contributing 7.2V 1350mAh. Unlike the CN, you do not have to manually connect these to two probes; instead, you can just insert them and move a “gate” back and forth to lock them in place. This “gate” can be in the left position, which allows the rightmost battery to be removed, the right position, which allows the leftmost battery to be removed, or the middle, which keeps both locked in place. When running on battery power, both batteries are used simultaneously (in parallel), as opposed to being used in series. They have aged well; I get over an hour and a half of combined use on mine.

The screen is a matte, color, passive-matrix LCD with an active WACOM Digitizer over the top of it. It does have pressure sensitivity, but I wasn’t able to get any programs to recognize this (likely a driver issue). There is an array of buttons to the right of the screen (0-9, period, dash, backspace, enter, Esc/Alt/Ctrl/Tab, and arrow keys). These appear to have NKRO (you can press as many as you want simultaneously), and I tested this by playing a race of the videogame Road Rash using only these buttons (and won on the first try, despite the motion blur of the passive-matrix screen). It was actually fun to play it this way; given the digitizer, however, this machine is obviously most ideal for Solitaire.

There is a single USB port on the top of the machine, along with a Contrast wheel for the screen, and the dual battery slots. On the right, you can find headphone, microphone, and DC Input jacks, along with a PS/2 port (labeled for both Mouse and Keyboard) as well as the recessed cavity for the WACOM stylus. There is also a plastic blank with a cutout for what I believe is an optional modem. On the bottom is an infrared blaster/receiver. On the left is an expansion port, and two PCMCIA slots that I confirmed are CardBus-capable.

The machine has an ESS ES1879 AudioDrive built-in, which I have always been fond of. Naturally, it doesn’t sound the best through the built-in monaural speaker, but it’s pretty impressive with a good pair of headphones.

Common Issues

The Achilles’ Heel of both of my Amity machines has been the CMOS/clock battery. This is soldered on, and once it runs out, the machine will no longer boot, or POST at all. Turning the machine on will result in a 1-4-2-1 beep code, and no video output or anything else! Since the battery is non-rechargeable, you cannot just leave the machine on for a few minutes to charge the battery, and then reboot it. However, this is also an advantage: Since the machine does not try to recharge the clock battery, you can simply clip the leads of the battery and solder a CR2032 holder to the pads, without worrying about a diode to prevent charging. On both my Amity CP and CN, this modification brought the machine back to life immediately!

(Pictures of Amity CN’s CMOS battery replacement. Click thumbnails for larger images.)

(Pictures of Amity CP’s CMOS battery replacement. Click thumbnails for larger images.)