Printers

Cracking Open the HP JetDirect EX Plus

HP JetDirect EX Plus

In this gallery, we will be taking a look at the HP JetDirect EX Plus Print Server (HP Part Number J2591A). Back in the 90's, before HP started putting network cards in their printers, they sold these devices to translate a network signal in to a then-standard LPT printer port. Although I don't know exactly when it was purchased, I can assume this particular device was created in the mid to late 90's, as we will see proof of later. This print server accepted both BNC "Thin-Net" connections as well as the then-emerging 10Base-T Ethernet network standard.

Cracking Open Tools Required:

  • Torx T-8 Screwdriver


Photos by Wally Bahny for © TechRepublic

18 comments
oldbaritone
oldbaritone

in Image 4 28F800 chip in image 11 is an 8Mbit flash memory (1M x 8bit)

Torpedo_62
Torpedo_62

I think that the entry on the back: AD: 0060B0251D6A Is the MAC address for the unit. I believe the TR number is related to the batch.

neon.moon
neon.moon

Them numbers are date codes on the chips and such. Where you are seeing four digit numbers starting with 96xx, those are year and week of the year manufacturing date codes. On the Dale resistor array, probably open collector pull-ups, the 472 indicates that the resistors have a value of 4700 ohms.

robo_dev
robo_dev

Nudge-nudge, check out the asics on that one....

alpha431
alpha431

Very much what a cracking open should be, clear ID on the ICs with basic info. Plus some speculation on function. Not the sexiest item but very well done & still interesting.

garibaldi69@
garibaldi69@

I have 10 of them running on Okidata 321T's. Still need those continous form printers for that ancient software. I used to have the three port one running in my home. Now I just have one color laser printer.

mark_pearson
mark_pearson

I've installed well over 500 of these over the years. Great device works with any centronics printer! We still have them in production. With the included software that came with the print server you can manage it as long as you have the AD # (this is the MAC address as others have confirmed).

TexasJetter
TexasJetter

I prefer to keep mine in the original sealed box :) Yes that is right, we purchased several of these years ago, and I recently found one new, still in the box and never opened. Do I hear $10 anyone? ;)

dstitt
dstitt

In frame #4, I think you'll find that the line labeled "AD" is the MAC address for this device. I'm curious what we learned by tearing down a thirteen-year-old print server. I have nineteen-year old laser printer I'll offer for your next surgery (you pay shipping).

matthew.smith
matthew.smith

I enjoyed this... i have used many many print servers in the past and still find them in use on older printers.... Thanks for the memories!

bikingbill
bikingbill

We have one still in service - one of the benefits of simple design? The AD number on the back is the hardware MAC address. I don't recognize the TR number. Its configuration page reports it was manufactured in 01/1997, which fits with your estimates.

Wally Bahny
Wally Bahny

I had assumed that the 96XX was some sort of date code, but I wasn't sure what the second pair meant. Thanks for the info!

robo_dev
robo_dev

for comparison, it would be neat to tear apart something like a new cell phone to show how much smaller the new components are.

Wally Bahny
Wally Bahny

Thanks for the props. I'm still relatively new to the cracking open scene. Sometimes it's just as fun to break old stuff as it is to break new stuff. :-)

Wally Bahny
Wally Bahny

That's some serious extra supplies. :-)

Wally Bahny
Wally Bahny

Thanks to you and all for the info on the AD number. MAC address makes sense. I guess AD stands for address?