We have recently dissected and dumped the Level 2 “Plus” version of HP’s PostScript cartridge series. This time, we will look at the earlier Level 1 “PostScript Cartridge”.
Article Series
There are two cartridges for the HP LaserJet series that add Adobe PostScript support. They differ in the PostScript Level:
| Year | Name | Description |
|---|---|---|
| 1991 | HP LaserJet PostScript Cartridge | PostScript Level 1 |
| 1991 | HP LaserJet III PostScript Cartridge Plus | PostScript Level 2 |
Note that the article on the Level 2 “Plus” cartridge is the main one. This article only describes the differences of the Level 1 cartridge to the Level 2 cartridge.
Cartridge
The cartridge is about 9×14 cm in size.
The front says
HEWLETT PACKARD
PostScript* Cartridge
ITC Avant Garde Gothic
ITC Bookman
Courier
Helvetica
Helvetica-Narrow
New Century Schoolbook
Palatino
Times
ITC Zapf Chancery
TIC Zapf Dingbats*
Symbol
33439Q ©Hewlett-Packard 1989, 1990, 1991HP
LASERJET
POSTSCRIPT®
The back says
Adobe and PostScript are registered trademark of Adobe Systems
Incorporated in the U.S, and other countries. Helvetica, Palatino and
Times Roman are registered trademarks of Linotype AG and/
or its subsidiaries in the U.S. and other countries. IT Avant Garde
Gothic, ITC Bookman, ITC Zapf Chancery and ITC Zapf Dingbats are
registered trademarks of International Typeface Corporation in the
U.S. and other countries.
Board
This is the very same board as used by the later “Plus” cartridge, except that it is fitted with only three instead of four ROM chips:
The ROM chips are:
- two 512 KB Toshiba TC534200P mask ROM chips
- one 512 KB Toshiba TC574200D-150 EPROM
Both types conform to the 27C400 pinout. The mask ROMs are marked with
© 1989-90 HP BOISE
© 1984-90 ADOBE
© 1981 LINOTYPE
and the EPROM is marked with
© 1986-91 HP BOISE
© 1984-91 Adobe
© 1981 Linotype AG
ROM
These are the verbatim dumps (adjacent bytes are swapped):
- 1818-4788, MD5 e2d740f3b15bfdf837b9385490e8dafd
- 1818-4789, MD5 1fe13fabb47f0719b9a840df8e5844e6
- 33439-60115, MD5 520d4f2e0ccf7f143fcdbe62f31792a2
This is the combined (byte-swapped) 1.5 MB ROM image:
HP PostScript Cartridge 33439Q ROM, MD5 929ba4050a8a48c3ed4761c3f9267837
The ROM image starts with a signature of “SYST” and the following messages at 0x30:
C V6.20 PSCRIPT
06.20
Copyright © Hewlett-Packard Company, 1991. All rights reserved.
(This part comes from the EEPROM.)
Just like the “Plus” cartridge, the ROM contains Adobe’s PostScript rasterizer (level 1 in this case) compiled for the 68000 CPU, the PostScript base fonts as well as some LaserJet-specific software (messages, errors and settings texts for the 15 char display in several languages).
PostScript Files
Like in the “Plus” cartridge, there is some PostScript source code in the ROMs:
(The missing %! file header has been added to the downloads.)
FONTPAGE
“FONTPAGE” is identical to the file in the “Plus” cartridge, see there.
TEST PAGE
“TEST PAGE” prints various internal printer settings which are unsupported by computer-based PostScript rasterizers, so the file has been patched to work with the the macOS 12.6 PSNormalizer.framework rasterizer (based on Adobe Acrobat Distiller 5.0):
STARTUP PAGE
Manuals and Extras
Future Work
Are there versions of this cartridge with different EPROM contents?