This article originally appeared in TidBITS on 1991-03-25 at 12:00 p.m.
The permanent URL for this article is:
Include images: Off

DeskWriter Problems

by Andrew Lewis

The Hewlett-Packard DeskWriter is a wonderful printer, combining 300 dpi print quality with street prices under $800. We even have a waterproof ink for it at long last! But a few other problems have recently cropped up. Unfortunately, even though the problems are relatively rare, HP has done a poor job of making the information available to dealers, who are the primary support for DeskWriter owners. In any case, here are the two DeskWriter problems and solutions that I know of.

People who use the Mac Plus under MultiFinder may experience strange crashes when trying to print to the DeskWriter. HP was aware of the problem as early as August. The problem was identified by HP and Apple as an "interaction" between the Mac Plus ROMs (HP claims this bug may also affect some SEs "which had the same ROMs," although I don't think that any SEs used the 128K Plus ROMs) and the older printer drivers supplied by HP with the DeskWriter.

Version 2.1 of the driver software (one for serial use, one for AppleTalk) corrects this problem. Oddly enough, HP does not guarantee that these new drivers are a complete fix. The people I talked to at HP's technical support said they "didn't have a Plus in the office" on which to test the fix. The update also fixes some other minor problems, including an incompatibility with Super Laser Spool from SuperMac. Getting the new version can be a bit of a pain - it's available in HP's CompuServe forum or theoretically from dealers, though neither of the two HP dealers here in Ithaca had the drivers before I did.

The other problem, quite rare and fairly unpleasant, concerns owners of the newer AppleTalk-capable DeskWriters. This bug pops up when the DeskWriter is used as a serial printer (as opposed to as an AppleTalk printer). After an indeterminate period of time, the printer refuses to work properly - the lights on the printer may flash, and the Mac may display an "Error Trap 10864" error code. The nasty result is that the printer won't print. Switching to the other serial port might help temporarily, but can result in another failure. The DeskWriter's hardware normally senses how it is connected to your Mac and switches itself into either AppleTalk or serial mode, as appropriate. Somehow this failure is begun by a change in the resistance of the Mac's RS-422 serial circuitry, which causes the DeskWriter to switch to AppleTalk, even though it is still receiving serial data which it cannot process properly while under AppleTalk mode.

According to HP, the problem appears with the Macintosh SE, II, SE/30, IIcx, IIci, and IIfx. Apple and HP agree that it is an Apple design flaw. This condition does not seem to prevent other serial devices from functioning properly, luckily. The fact that this condition of the Mac's serial port affects only the DeskWriter probably accounts for much of the lack of knowledge about the problem on the part of Apple dealers. It appears that HP designed the DeskWriter to conform to the standards of the component circuitry used by Apple in the Mac's serial port without taking into account any quirks of implementation on Apple's part. HP's approach to the problem of configuring the printer automatically is to my knowledge unique, and unfortunately generates a unique problem. HP is clear about the fix - avoid the whole problem by using your DeskWriter in AppleTalk mode. This requires only LocalTalk or PhoneNET cabling, which can be had for around $60. You don't need to be on an existing network or have a fileserver or anything of that nature. If you use LocalTalk cabling, the HP AppleTalk driver, and keep AppleTalk turned on, everything (including other serial devices) should work fine.

Assuming that not everyone would like that answer, considering that it increases the printer's cost by about 10%, I checked around about what to do. My local dealer (for both Apple and HP) was unaware of the problem. I called Apple's 800 technical support number and received no information. They told me that they dealt with such matters on a "case by case basis," which meant that they would not tell me anything regarding warranty coverage and such unless my Mac actually developed the problem and I brought it to an Apple dealer. They also were unable to confirm or deny that Apple would release a statement on the problem as HP claimed they would. [Editor's note: I later found Apple's and HP's statements on AppleLink; they both pretty much said the same thing.] However, HP's technical support people provided some information. They told me that HP and Apple had investigated and isolated the cause of the problem. According to HP, Apple dealers should know about the problem since it is in their "Apple Service Manual," and they will fix your Mac if the serial port fails. I couldn't get a firm answer, but it seems that AppleCare or your warranty will cover the repair costs. [Editor's note: Apple's statement on AppleLink confirms this answer, and added that if the Macintosh is not covered that the dealer should discuss the problem with "Technical Operations." I didn't pursue the matter further.]

So what does it all mean? HP has solved both problems but did a lousy job of telling anyone. Even if these problems are relatively uncommon, people who experience them, particularly the second one, could go through a time-consuming, frustrating repair experience. For a repair person who doesn't know of the fix, diagnosis would be difficult, tedious, and potentially expensive, since both the Mac and printer would appear to work fine independently. All of the information above is the result of a lot of phone calls to Apple, HP, and my dealer, as well as the kind indulgence of Kris Stark and his CompuServe account. That sort of research should have been unnecessary. HP should distribute their new drivers and statements on other commercial services such as America Online and GEnie, as well making the information known on Usenet. Even more important, HP should definitely make more of an effort to see that their dealers have the latest information regarding their products.

Information from:
Mark H. Anbinder -- mha@memory.uucp
Jeff, Debbie, and Janice at HP Tech Support -- 208/323-2551
Apple Technical Support -- 800/776-2333
Tonya Byard -- TidBITS editor (for the editor's notes)