Rockbox mail archive
Subject: Re: System Tray USB Icon
From: Fred Maxwell (rockbox_at_anti-spam.org)
Glenn Ervin at Home wrote:
> I don't know why anyone would want to hook a printer up via USB when they
> have a perfectly good parallel port.
Because they can disable the parallel port and avoid it tying up I/O
ports, DMA channels, and interrupts. They may prefer a cable that is
smaller in diameter than a horse's leg. They may not like having to
choose between "Normal", bi-directional, ECP, EPP, EPP+ECP, etc. They
may like the idea of running one cable over to a USB hub that runs their
scanner, USB modem, and fax. They may be using their parallel port for
a chip programmer. Maybe their printer only supports USB. Maybe they
they have a laser printer on the parallel port and want to hook up a
color inkjet. Or maybe they have one of the newer systems with no
legacy ports (parallel, RS-232 serial, keyboard, mouse) and only USB.
> I sure would not want to waist my USB port on a printer which doesn't need
> the speed of the USB anyway?
First, let's do some math: Let's look at a monochrome 600dpi, full
page, color image. That's about 600 pixels * 24 bit color * 8 inches *
10.5 inches. That's 400KB of data without accounting for communications
overhead. Bump that up to 1200dpi, and you're over 1.5MB of data. Are
you suggesting that USB ports are better reserved for mice and keyboards?
> Do you have a parallel cable for your printer?
> If so, use that instead of the USB.
I disagree. USB is a far superior interface for high-resolution
printers. Live with the little USB icon instead.
Page was last modified "Jan 10 2012" The Rockbox Crew