HP95LX, 100LX, 200LX Technical Details and Trivia


  • a PCMCIA-compatible PC Card slot (v1.0 Type II on the 95LX, v2.0 Type II on the 100LX and 200LX). Type II means you can use cards with a thickness of 3.3mm or 5mm. This type of slot only allows for "memory-mode" cards, not "device-mode" cards.
  • an infra-red eye capable of transmitting and receiving data
  • an RS-232 serial port (4-pin, 3-wire non-standard connector on 95LX, 8-pin, full RS232 serial port (100LX, 200LX)
  • a backup battery tray (backup battery is a CR2032 coin cell)
  • a power supply socket -
  • a battery bay - fits 2 x AA batteries - make sure you insert the batteries the right way or you can easily destroy the motherboard!!!

Technical Facts

  • The motherboard of a 512K 95LX and 1Mb 95LX are identical - the only difference is that one of the 512K memory chips is missing. This allows for a relatively easy upgrade.
  • The 200LX has the capability to charge Ni-Cd batteries, which the earlier versions do not.
  • The ASIC chip in the 95LX, called "Hopper", takes a lot of responsibility - it acts as the display controller, keyboard controller, UART, interrupt controller, interval timer, real time clock, A/D converter, tone generator, memory management, mapping, card port support, and more.
  • Able to support PCMCIA v2.0, this allowed the 200LX to support PC flash disk cards with capacities of 5Mb, 10Mb and even 20Mb.
  • One device you can use in the PCMCIA slot is a modem from NewMedia.
  • According to www.hermocom.com, the 95LX was designed to work only with SRAM cards for storage. These cards are available in capacities up to 4 MB (or are there even 8MB SRAM cards?), but they are fairly expensive. The 95LX can handle up to 2 MB without any problem. For larger capacities, you may need the acecard driver. SRAM cards need a battery to keep their data; some cards use a CR2025 lithium coin battery, whilst some have an internal rechargeable battery which is charged by the device they are used in.
  • To use ATA flash cards in the 95LX, you need to install a special driver from Sundisk - see Software section for download.
  • Sadly, none of the HP palmtop range came with a backlight to improve visibility in low light conditions, probably because HP thought this would have reduced battery life dramatically. Some owners however, have added their own (see Technical section for the how-to guide!).
  • The 95LX can support a maximum of 32Mb RAM due to MS-DOS v3.22's restriction on 32Mb disk partitions.
  • You can decode the 100LX prototype serial number as follows: The first two letters are the location of manufacture (SG=Singapore), 3rd digit is the year of manufacture (3=1993), 4th and 5th digit are the week in the year of manufacture (05 = 5th week, aka first week in February), and digits 6-10 are the serial number in consecutive order of manufacture (00061 = 61st model built).
  • You can perform a system self test by pressing Esc + On when the palmtop is switched off. Be warned though: the Plugin card test may destroy the contents of any cards plugged in - it is really designed only for SRAM cards.

95LX Motherboard

(Hover your mouse over the circuit board for a description of the components)

The above is the top-side of a 512K 95LX motherboard


And here is the underside of the same board

Model Numbers

The HP Palmtop range consists of the following model numbers:

95LX (512K RAM) - HP F10
95LX (1Mb RAM) - HP F10
100LX (1Mb RAM) - HP F1060A
100LX (2Mb RAM) - HP F1061A
200LX (1Mb RAM) - HP F1060A
200LX (2Mb RAM) - HP F1061A

95LX optional accessories:

Worldwide AC Adapter - HP F1011A
Accessory Cradle - HP F1007A
DOS Connectivity Pack - HP F1001A ($99.95) - transfer files between your 95LX and IBM-compatible PC. Includes necessary datacomm software, a serial interface cable, and cable adapter to make a 9-pin or 25-pin connection to the PC.
DOS-compatibile cable - HP F1015A
Mac-compatible cable - HP F1016A
Connector/Adapter Kit - HP F1023A
Serial Interface Cable - HP 82222A ($35.00) - connect the 95LX to a serial device such as a printer or modem. Cable only. This cable is included with the F1001A Connectivity Pack.
Optional ABA Adapter for US/Canada - HP 82241A ($15.00) - conserve battery life with this AC adapter. 110V 50-60Hz.
Serial Cable Adapter Kit - HP 82224A ($15.00) - adapts the serial interface cable - kit includes a printer adapter and a modem adapter. Each has a 9-pin male connector and a 25-pin male connector. 128K RAM Card - HP F1002A ($149.95)
Mobile Data Link to NewsStream Receiver - HP F1006A ($119.95) - Connect the 95LX with the NewsStream receiver using this product's cradle and software. Electronic mail can be received instantly and wirelessly in the US, via national regional, or local radio paging services. Direct the messages to update your appointment schedule, spreadsheets, lists or memos.
NewsStream Receiver Motorola's advanced information receiver ($299.00) - NewsStream can receive and store wireless messages in its 32Kbytes of RAM even when it is not connected to the HP 95LX. A green light flashes to alert you that messages are waiting.
512K RAM Card - HP F1003A ($299.95)
1Mb RAM Card - HP F1004A ($599.95)
5Mb 5V Flash Disk Card - HP F1018A

100LX/200LX optional accessories: Worldwide AC Adapter - HP F1011A
Accessory Cradle - HP F1027A
DOS Connectivity Pack - HP F1021B
DOS-compatibile cable - HP F1015A
Mac-compatible cable - HP F1016A
Connector/Adapter Kit - HP F1023A
5Mb 12V Flash Disk Card - HP F1012A
10Mb 12V Flash Disk Card - HP F1013A
20Mb 12V Flash Disk Card - HP F1014A (available from 200LX launch onwards)

HP Software:Dictionary/Thesaurus Card - HP F1005A ($149.95) - Includes 116,000 words and word forms, and over 500,000 acronyms. Provides spelling correction in the 95LX Memo Editor.





  • If the screen flickers, it's probably caused by the power drain from the Flash card you have inserted!
  • The Infrared port of the 95LX works only up to a data rate of 2400 baud, but the IR diode is much more powerful than the IR diodes of the other palmtop models. So it can be used very well for remote-control the TV or HiFi using REMCOM
  • The 95LX runs on 5V DC internally, whereas the 100LX and 200LX run on 3V internally. This helps keep battery life good despite the additional drain from the higher resolution screen, and heavier processor.
  • The 95LX's CPU, the NEC V20, is actually able to run at up to 10 MHz, but the crystal oscillator (clock) slows it down to a cooler-running 5.37 MHz.
  • In both the 100LX and 200LX, the charging mechanism is rather strange - it fast-charges the rechargable batteries inside the unit (if you're using rechargeables) for 6 hours every time you enable charging (or insert the AC adapter when charging is enabled) then it trickle charges the batteries continuously thereafter. A tool called ABC/LX, written by D&A Software, can be downloaded here that sorts out the charging to work properly and without hassle.


This page was last updated on 8th September 2014.

512K RAM chip