HP Integral PC Manuals?

It's certainly aa beautiful machine. Is it a plasma display, though?

I thought I read it was an electroluminescent panel (basically exicitng a solid phosphor maaterial in an alternating electric field). I must admit that the display is the one part of the machine that I know ittle about, I did dismantle the display module in one of my 2 Integrals, there's a PCB on whcih most of the ICs are custom and unidentifiable, so I didn't go much further. The display, of course, was not made by HP. The beast place to look for manuals for old HP machines other than handhelds is http://www.hpmuseum.net/. I think at least the (l)user manual is there. But be warned that 'my' scheamtic there is an early version, and I know I made an error in the address decoder circuit (basically I miscounted the address pins on the CPU at one point). The HPCC CD-ROM contains an updated version. I ahve never seen an HP techical manual for this machine, but would like to. Low level programming info would certainly be interesting. Actually, most of the time the dive is suffereing from hardened grease. It doesn't need lubricating, it needs taking apart and cleaning. I wrote an artice about this (in general, not Integral-specific) in the HPCC journal last year, I susepct you can purchase a copy of the appropriate issue from HPCC.

Anyway you must have been inside the machine. How far did you get? The order I dismantle the machine in is : Remove the ROM cover and take out the HP-UX ROM. Remove expanison cards, then 2 screws and the back cover Remvoe the rear screening plate (6 screws and a little plastic peg thing) Remove the floppy drive (unplug the 2 cables, then 3 screws and slide it out. Don't lose the eject button and spring. Undo the screws and free the logic assembly, Reach under it and unplug the cable from the display. Unplug the cables from the lower edge of the PCBs going to the fan and PSU/expansion box. Remove the 4 screws holding the front screen ot the logic module and unplug the THinkjet cabling. Then the whole logic unit comes out. Separate the logic boards from the chasiss plate. Rmwove the PSU/expansion box -- take off the earthing nut on the expansion backplane, then the 4 screws at the rear sides and slide it out Take of the nuts and screws and take the cover off the PSU/expansion box. I find it easiest to lift the cover up as far as it will go, then unbolt the HPIB conenctr from the back and take the cover off with the HPIB cable. Remove the Thinkjet controls. First remove the logic assembly mounting spacer to free the earthing tab. Then one screw and take the control out. Take out the printer mechanism. It's just a few screws. I normally don't need to remove tbe display.

Anyway, the circuitry is a mix of standard and HP custom parts. The only chip I've not seen used elsewhere is the display controller. Other HP ASICs includ the HP-HIP interface chip, the Thinkjet controller, its RAM and ROM, and the HPIL chip that interfaces that to the rest of the machine. The keyboard connector is HP-HIL. There are 2 connectors, but they form part of the same HP-HIL chain, so you're limited to a total of 8 (or is it 7) devices. There's some circuity on the logic board to complete the chain if you honly have one connector in use (as is often the case, you just have the keyboard). It doesn't matter which connector you plug the keyboard into. The Thinkjet printer is conventional-ish. It uses the normal Thinkjet procrssor, Font ROM and RAM (which communciate with the processor using a Saturn bus (!)). The Thinkjet processor has a built-in HPIL interface, hence the 1L3 HPIL chip next to in o the board. YEs, there's a tiny HPIL loop to link the printer to the rest of the machine. The printer mechanism is standard but for the fact hat the cables are a lot longer than those in a normal Thinkjet. This is a particular problem wit hthe carriage flexiprint, which is thus not the same as the one in any other Thinkjet. And as is well-known,Thinkjet ink is corrosive. Never leave a cartridge in an Integral. I think if I ever need to replve the flexiprint in my Integrals, I'd use anormal-length one and kludge up some kind of extension. Do you ahve any expansion boards? The most useful ones are a memory expanison (1M is the largerst HP one I've seen, I posted an article here a couple of months back about expanding the 512K one to 1M), and an RS232 board (in fact I bought a second Integral fairly recently mainly to get that board). I also have an internal 300/1200 baud modem and a ROM/EPROM drawer for mine, but not enough slots :-)

The maion prolems with this machine are, IMHO : Not enough memory, you really need a 512K or 1M card No serial port -- the RS232 board is something you want to find. And therefore not enough slots, if you add memory and RS232, you have no slots left. There was an expansion box, but I've not found one yet. No hard disk. Yes, you can add an external HPIB hard disk, but that rather defeats the point on a portable machine.

-tony