Lexicomp LC-8620 from Abstract RandD Inc.

Review of Lexicomp MS-DOS palmtop.

This is a Taiwanese built US designed clamshell palmtop with a subset of Microsoft's MS-Dos 5 and a small number of utilities in EPROM. This is at the limits of palmtop size, being 228mm (9") by 118mm (4.75") by 32mm (1.3") thick, giving a volume of 860 cc. The weight is 765 gram.

The display is a 640 pixel by 200 pixel LCD, a total of 128,000 pixels, configured as CGA, with 4 gray levels. The display size is 172mm by 64mm, or 183mm diagonal. The standard 8 x 8 character set is thus 2.15mm high and 2.56mm wide per character. LCD adjustment is via a potentiometer control, not via software.

As with most keyboard palmtops, the keyboard occupies almost all the body size. The key spacing is 14.8mm (a standard IBM computer keyboard is 19mm). There are 78 keys. The numeric keypad is part of the alpha keys, and can be switched on via the numlock key. The cursor keys are in inverse T, and the Fn key is used to access home, end, and pg up and pg dn. There are only 10 function keys, with F11 and F12 being accessed via the Fn key. A Ctrl key is alongside the A, and there are two Ctrl and two Alt keys available. The cursor keys can be used to emulate a mouse, toggled on and off via a Fn key. The "mouse" worked fine with my MS-Dos software. The keyboard includes a recessed "reset" switch, which can only be reached with a fine pointer, such as a paperclip.

The processor is a Chips and Technology 8680, running at either 7 MHz or 14 MHz, but only as a very fast 8086 CPU. No AT or 386 CPU actions are available. An EMM memory driver is provided in EPROM.

Memory is 2 megabyte, and the size to treat as CPU memory can be selected by pccemm.sys. Ramdrive.sys can then be configured to allow some of this to be used as a ram drive, optionally not cleared on reset. The standard BIOS allows 704 kilobyte of system memory, and if you can make effective use of emm, you would thus have about 936 kilobyte of ram disk available. The ram disk size can be increased, by reducing the memory allocated to emm.

A Type 2 PCMCIA card slot is included. The system does not include PC Card Socket Services, however 1 MB and 2 MB SRAM cards from FDK, Grid, Apple Newton and other systems worked fine. Flash memory cards from a Newton do not work.

The model I tried includes a 40 MB Hewlett Packard 1.3" Kitty Hawk drive. As this draws over half an amp on spin up, battery life while using the hard drive is not spectacular. I run my applications almost exclusively from Ram Drive and PCMCIA card, with the hard drive for long term storage and infrequently accessed applications and data.

The Kitty Hawk 1.3" hard drive came out in 1992, and measures 2" x 1.44" x 0.4" It can operate through a 150g shock (5 foot fall onto a concrete floor), and retracts the heads whenever it senses a severe shock. Rated for 100,000 start stop cycles. It spins at 5400 rpm, with a 5.6 msec average latency, average 15 msec seek time, and 1100 kbytes/sec transfer rate. Draws 2.2 W at startup, 1.6 W on read/write, 15 mW in sleep. 750 msec to spin up from sleep. Uses three surfaces on two glass substrate platters.

There is a standard 9 pin RS232C serial port, and a standard 25 pin D parallel printer port. A Rockwell 2400/9600 fax modem is included, with a standard US RJ11 phone port. Hayes commands from terminal software such as Kermit works fine on this as Com 2.

There is no provision for an external floppy drive or hard disk. I had no trouble using a parallel to SCSI adaptor to run an external SCSI hard drive, however Microsoft's MSCDEX software for MS-Dos 5 was not compatible with the Microsoft MS-Dos 5 provided in EPROM, so I have not been able to test whether a CD-Rom will run.

The Lexicomp chews more power from the wall socket than some (less on batteries, but these figures give a good indications of what is happening. With nothing much happening in suspend mode, it draws 74mA. A blank display draws 140mA. A directory of the rom runs 210mA. Starting up the hard drive jumps up to 1.3A, while a directory of it runs 0.54A. In turbo (double speed) mode, that jumps up to 0.62A. Running the serial port draws 143mA, as does the parallel. Running both uses 144mA. Changing the display from lighter to darker only changes the power drain a few milliamp.

Sys Info says the (7 MHz Chips and Technology 8680) CPU is running at 42 MHz. Dos memory is 704k. Landmark v3.33 shows it running at 9.3 MHz, or 4.9 XT (in turbo, 19.8 MHz or 10.5 XT). Additional drivers in memory are absmouse and emdrv, and there are bios extensions at CE00, E000, and E800. There is a power$ at 0081:0002. PC Benchmark gives a 5.7 rating (8MHz AT=4.4) (in turbo, 11.7). Disk benchmark is 3.6 (turbo 6.5). Actual results were 15.5ms average seek, 2.15ms track to track, 142.6k/s data transfer speed. Overall result 9.3 (vs 3.7 for an 8MHz AT). Calmer Utilities compatibility rating is 100%. Checkit rates it as a 38.38 MHz XT, running at 1700 dhrystones (turbo 3489 or 78.27 MHz). Whetstone rating is 32.1k (turbo 64.6k). Video bios runs 991 cps (turbo 2084 cps), 21790 cps direct Z(turbo 40375 cps). Disk transfer rate is 135.8 kps, 17.1ms average seek, 4.8ms track to track.

The model I checked was S/N 0012969, purchased in 1995. I've seen some complaints about QC problems on the net, and Abstract RandD now seem to have only a single store (not retail).

Eventually some chemical reaction occured in the painting of the case, which went incredibly sticky, and came off on everything. I ended up unable to use the machine. I guess I'll attempt to scrape the paint off the plastic of the case.

buy that?
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