HP IPC (update)

From: Vassilis Prevelakis <vp_at_mcs.drexel.edu>
Date: Sat Apr 13 17:49:01 2002

Joe <rigdonj_at_cfl.rr.com> wrote:
> One of the options for the IPC is Technical BASIC in ROM.
Yes, looking closer at the ROM cartridge I see that the TechBASIC code and
version is on a sticker placed over the (larger) HP-UX sticker.
I must consider myself really lucky for getting that ROM, otherwise I'd
have to write shell scripts to program the IPC :-)

I opened the ROM pack and it contains two PCBs, the larger contains the
interface holes (where the pins sticking up from the IPC motherboard make contact)
and contains the OS ROMs (it says OS ROM on the PCB), while the smaller
sits on top of the OS PCB and contains the TechBASIC ROMs (it says OPTION ROM
on the PCB).

Each PCB contains two pairs of ROMs. OS are ROM0 (high and low) and
ROM1 (High and Low). The TechBASIC are ROM2 (H and L) and ROM3 (H and L).
Obviously since the ROMs are 8bit and the 68000 is 16 bit you need
a pair of ROMs for each bank. The OPTION ROM PCB has a very
straightforward interface since it contains just the 4 ROMs.

I am not sure of the capacity of the ROMs but I wouldn't think that they are
likely to be larger that 64Kbytes each. Now that we can get far larger PROMs,
if the images of the SE ROM were available, would it be possible to construct
an OPTION ROM PCB with everything in it?

> [...] C compiler (I think it includes an assembler) [...]
Thats great news I was thinking about setting up gcc on my OpenBSD system as
a cross compiler for the IPC, but in that case I'd need to recreate the
system libraries and include files. Is there any way you can put them up
for ftp?

ard_at_p850ug1.demon.co.uk (Tony Duell) wrote:
> HPIL is a loop, not a bus (strictly).
Guilty as charged, I was over simplifying to the point of being wrong.
I have a collection of HP-IL calculators and peripherals so I've had
first hand experience of things failing to work because of breaks (or
powered down devices) in the loop.

> Be careful. External HPIL ports are supposed to be transformer-isolated
> (using a special HP pulse transformer module, 9100-4226 IIRC). Every
> HPIL device with the external connector will contain said transformer.

yes I've been thinking about where to get such a transformer (and the dual
HP-IL socket). I was thinking of cannibalizing an HP-IL module for the HP-41.

> Is this the Thinkjet cartridge (little clear plastic thing with a black
> rubber ink sack inside)? If so, then the printer electronics is likely to
> be close to the Thinkjet as well
Its a Thinkjet all right. I have both the HP-IB and the HP-IL versions of the
Thinkjet and the mechanism and electronics of the printer in the Integral
are very close to the HP-IL version of the Thinkjet.

> If you have problems, then I've repaired enough Thinkjets to be able to
> offer comments...
Apart of having to clean the printer compartment of ink - unfortunately
the IPC was shipped with a print cartridge installed :-( it works all
right.

However, the instructions for cartridge replacement in the HP-IL Thinkjet
manual, imply that a small pad is supplied inside the cartridge packaging.
This pad is supposed to be inserted in front of the the cartridge on the
print-head. The new ink cartridges I have purchased do not have this pad
and each time the machine powers up the Thinkjet deposits a blob of ink on
the paper. Anybody knows of what can be used as a replacement for this pad?

> This surprises me. A 1.44M drive _using 720K disks_ should have no
> problems.
Me too! I am routinely reading and writing 9114 floppies on my laptop
but the IPC drive is particularly difficult. In the beginning I was really
lost because I would prepare floppies and the IPC would just say no. At
one point I thought there was something wrong with the drive itself. Once
I got the 720K drive for my PC, the IPC capitulated.

One interesting point is that using my "Unix" system (OpenBSD 2.9)
I can dd images on a new 720K diskette (i.e. formatted for the
IBM-PC) but the OpenBSD system barfs when I try to do the same on
the same floppy once it has been formatted by the IPC.

I have excluded alignment problems because I also have an 9122D external
drive and have done tests with floppies prepared on these drives.

Now that the IPC is usable, I am going to do more tests once I have some
spare time.

**vp
Received on Sat Apr 13 2002 - 17:49:01 BST