Data Transfer on an hp 200LX

I Recently acquired an HP 200LX. For those of you too lazy to click the link, The 200LX is a PDA and a PC/XT in one pocket sized case.

It was released in the early 90s, a simpler time, when people had serial ports on their computers. It came with a null modem cable with a special plug for the non standard shape of the serial port, and software to transfer files from DOS, windows 3.X and windows 95.

And for a time things were grand. Windows evolved, as it is notorious for doing, Computers grew up and lost their serial ports, and slowly the little bubble of HP's perfect transfer scheme was breached.

But then, a miracle from the heavens, HP releases Transfile200. A majestic application that works on even the latest incarnations of Redmond's beast, even over USB (or for the adventurous, bluetooth).

Of course this all assumes that you still have the original null-modem cable, or any cable that will plug into the 10 pin slot on the palmtop. I, sadly, do not.

At this point things get interesting. There are three options for file transfer assuming that you don't have the connectivity cable:

1. Buy a cable, alot of websites (maybe even HP) still sell them.
2. Build a cable
3. Get a CF card and CF to PCMCIA adaptor.

Of the three, the Compact Flash card is by far the simplest option. According the the Documentation I have been able to find, any adaptor will work, and *most* CF cards are supported (although some need a special "acecard" driver, available here.)
Sadly, the SanDisk Ultra II CF cards Do not work with the Palmtop. This is probably because they are based on a newer technology (NAND Flash, or some such nonsence.)

So, that was a waist of $30 (Card + Adaptor), but we live and learn.

Since buying a cable from HP would have been too easy, I decided to subject myself to a little torture, and to build one myself.

The short version: The serial port on the palmtop is the same as a regular DB9 port, but smaller (the extra pin is another ground), you need to wire up a null modem cable, and then connect it to your computer.

The long version:

I ripped the serial port out of an unused computer case, for whatever reason there was one in the front with a nice little ribbon cable coming out of it.

I stripped the motherboard connection off of the wires, leaving just a little gold piece that slides onto the pins of the palmtop.

I put each wire onto the appropraite pin, depending on the context. ( [1-1 2-2 ...] for a mouse or other standard serial device)

The pinout of the LX looks something like this:

IR/ Backup Battery [12345 ] Power Port
[678910 ]

To do file transfer the wires need to be aranged like this:
Pin 1 of the cable to Pins 7-8 of the palmtop
Pin 2 of the cable to Pin 3 of the palmtop
Pin 3 to pin 2
Pin 4 to pin 6
Pin 5 to pin 5
Pin 6 to pin 4
Pin 7 to pin 1
Pin 8 to pin 1
and pin 9 can remain unconnected.









For those keeping score, this is actualy cheating just a little bit, but it works, so don't complain.

File transfer is slow (9600 Baud!) but it works, just don't wiggle the palmtop while its going, or things will come grinding to a halt.

Now those of you who actually read this far may be thinking to yourselves, but what good is it all?. All in due time, all in due time.