On May 19, 2009, at 6:06 PM, Dr. Gerald N. Johnson wrote:
There has nearly always been serial to parallel converters. Both
work in
1 byte chunks because RS-232 serial is usually asynchronous and has 3
handshakes for hardware handshaking. The vintage parallel port has 8
bits out and four back in its classic form but more recent hardware
can
change the output register (its TTL levels all the way to the printer)
to an input register for relatively slow bidirectional data, often
used
with a scanner. USB works both ways, I don't know about the USB to
parallel cables. With several computers not supporting USB, I've
looked
at seeing if one will work parallel to USB, but haven't spent the time
and money to find out. Fortunately I found a laser printer (HP 2550L)
with both USB and parallel ports which I believe was the last one
made.
I bought it at an Office Depot off their demonstrator shelf and will
soon have to replace some color cartridges but its run maybe three
years
for me on the original small ones.
I've gotten around that the "easy" way. With several computers here, I
have one running a modern version of Linux and CUPS. The computers
connect to it and the CUPS software handles translation from
postscript if needed, and queueing, so more than one person can print
at the same time and the jobs are kept seperate.
At one point had was part of a hardware/software design effort and we
had connected to various CUPS servers laser and inkjet printers
upstairs where we live, a laser and inkjet printers and an HP plotter
downstairs where I worked, and an inkjet printer at a remote location
via a VPN. The printers and plotter were a mixture of serial, parallel
and USB.
Vista has not achieved universal acceptability because of its demand
for
new hardware and lack of support of working legacy hardware like
serial
and parallel ports, plus the need for replacement of nearly all the
applications software with accompanying retraining and cost. It may
not
be the best OS for using applications created for the fun and not by a
huge committee with access to the resources needed to meet Vista
interface requirements which means it may not be good for ham
applications at all.
One of the "features" of Vista was that it did not have hardware
support for old devices and programing support for some of the older
versions of Windows. It was designed with buying everything new. I've
stuck with XP and still have my copies of WordStar 3.3 (PC DOS version
of a CP/M program circa 1980) and WordPerfect 4.2 (circa 1986), both
of which I use about once a year.
Most new computers do not come with serial or parallel ports nor
floppy drives. New radios will have to come with USB or Ethernet ports
for computer control (doesn't the Omni 7 have an ethernet port?)
Either that or the hot topic on 2m will be keeping old computers
running.
Geoff.
--
geoffrey mendelson N3OWJ/4X1GM
Jerusalem Israel geoffreymendelson@gmail.com
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