Just thought I would pass this on. I got USB happy, so I bought a USB-Parallel connector for my Canon BJC-6000 Bubblejet printer.

At first, it didn't work so I called Canon (long distance and SLOW). They said that it would only work with their $70.00 USB kit!!

I remembered something about USB-Parallel connectors not being able to be bi-directional, so I turned that option off in my printer settings and wa-la it worked! Shame on Canon.

Anyway, the moral of this story is that I realized the USB cable wasn't going to speed up the printer. It can only print as fast as the cartridge can scoot across the page. I am also assuming that the bi-directional capability is needed. Otherwise, how would the printer be able to alert you on the screen as soon as it ran out of ink?

Ideas anyone?

Later, Jerry http://www.members.home.net/garagekit/index.htm

-- Jerry Buchanan (garagekit@home.com), September 15, 1999

Answers

If I'm not mistaken, the bi-directional capability of the printer port has always referred to the ability to pass a full byte or a half byte, a nibble, in BOTH directions ON THE DATA LINES. The signals for Paper Out and other hardware printer interfacing were originally uni-directional, but the information flowed --> to the computer. In standard mode, even on the new ports, they should still be there or at least set up and emulated that way. I'm not sure how Canon implemented their communications regarding ink tank status, but if they intended it to operate from a standard printer port as well as an EPP or ECP configured printer port they might have used a communications protocol(a method) that allowed for this communication through the normal status lines like Busy, Paper Out, etc. If it only works with ECP or EPP mode you may have a problem, if you can't set the USB->Parallel coverter up for that.

My suggestion, if you're really curious, would be to have a look at the manual for the printer and see if they state any specifications about the printer and the interfacing signals. Epson was always good about this -often going into detail unheard of with consumer devices, perhaps Canon obliged. The only other thought that comes to mind is to check out a few electronics sources on the web. There's been a lot written about parallel port interfacing in the last couple of years. Those references will explain it all if you care to read them.

Try: www.lvr.com for links and info concerning serial, parallel and USB interfacing and some well written info about how most things like that work. The site belongs to Jan Axelson, an author and frequent contributor to electronics magazines. I'd recommend her "8052 Basic Microcontrollers" Book to anyone interested in building and interfacing a pretty powerful microcontroller programmable in a simple language like Basic or in C & assembly. It's not a "compact car" PIC chip, but really more of a "cadillac" with compact car relatives to boot! Sorry, if the above seems out of place here, but there must be a few other technoids reading this forum? :-)

-- Gerald Payne (gmp@francorp.francomm.com), September 16, 1999.