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Universal Parallel Bus -- why not?

Started by GreenXenon March 20, 2010
"krw@att.bizzzzzzzzzzzz" <krw@att.bizzzzzzzzzzzz> wrote in
news:dl2aq5dumrb6r3bitljlphfj85dnvbna1q@4ax.com: 

> On Sat, 20 Mar 2010 07:33:19 -0700 (PDT), GreenXenon > <glucegen1x@gmail.com> wrote: > >>Hi: >> >>I keep hearing about Universal Serial Bus [USB]. Why hasn't a >>Universal Parallel Bus [UPB] been implemented yet?
because cables for them would be far more complex and costly. How many bits were you considering for your "universal bus"? A 32 bit bus is going to need 32 wire pairs(signal and GND) or 32 coaxial cables of equal length,along with clocks,power and grounds. And now we're at 64 bit buses. Just look at the old printer cables. TV stations had the same problem when they went to digital video.and they only used a 10 bit bus.
> > It has. It's often called the "Printer Port". > >>Wouldn't a UPB be faster than a USB at the same clock rate?
Yes. ..but....more expensive,complex,and more prone to breakage. Also,fewer cables could be run in the same ducts.
>>If so, >>this would mean the same speed with less energy comsumption. Right? > > No. and HELL NO. >
MORE energy consumption,because your driver port has to drive all those outputs,instead of a single output. TANSTAAFL. -- Jim Yanik jyanik at localnet dot com
On Sat, 20 Mar 2010 18:47:15 -0500, Jim Yanik <jyanik@abuse.gov> wrote:

>"krw@att.bizzzzzzzzzzzz" <krw@att.bizzzzzzzzzzzz> wrote in >news:dl2aq5dumrb6r3bitljlphfj85dnvbna1q@4ax.com: > >> On Sat, 20 Mar 2010 07:33:19 -0700 (PDT), GreenXenon >> <glucegen1x@gmail.com> wrote: >> >>>Hi: >>> >>>I keep hearing about Universal Serial Bus [USB]. Why hasn't a >>>Universal Parallel Bus [UPB] been implemented yet? > >because cables for them would be far more complex and costly. >How many bits were you considering for your "universal bus"? >A 32 bit bus is going to need 32 wire pairs(signal and GND) or 32 coaxial >cables of equal length,along with clocks,power and grounds. >And now we're at 64 bit buses. >Just look at the old printer cables. > >TV stations had the same problem when they went to digital video.and they >only used a 10 bit bus. >> >> It has. It's often called the "Printer Port". >> >>>Wouldn't a UPB be faster than a USB at the same clock rate? > >Yes.
No. Skew.
>..but....more expensive,complex,and more prone to breakage. >Also,fewer cables could be run in the same ducts. > >>>If so, >>>this would mean the same speed with less energy comsumption. Right? >> >> No. and HELL NO. >> > >MORE energy consumption,because your driver port has to drive all those >outputs,instead of a single output. > >TANSTAAFL.
On Mar 20, 7:33=A0am, GreenXenon <glucege...@gmail.com> wrote:

> I keep hearing about Universal Serial Bus [USB]. Why hasn't a > Universal Parallel Bus [UPB] been implemented yet?
It has been done, twice. IEEE-488 for instruments, and SCSI for small computers. Expensive cables made IEEE-488 a boutique item, and SCSI (which got up to 320 MBytes/sec) was usually kinda high-end Most Macintosh computers from 1986 to 1998 used SCSI. Parallel ports DO NOT COUNT, because they aren't a bus; the early ones weren't even bidirectional, and there was never any good support for more than two connections. Bus, from 'omnibus' meaning 'for everyone' implies that all bus signals are served by all devices, not just two.
On Sat, 20 Mar 2010 07:33:19 -0700 (PDT), GreenXenon <glucegen1x@gmail.com> wrote:
>Hi:
>I keep hearing about Universal Serial Bus [USB]. Why hasn't a >Universal Parallel Bus [UPB] been implemented yet?
>Wouldn't a UPB be faster than a USB at the same clock rate? If so, >this would mean the same speed with less energy comsumption. Right?
nope. Serial is faster nowadays. Compare SATA-300 to PATA-133.
whit3rd wrote:
> On Mar 20, 7:33 am, GreenXenon <glucege...@gmail.com> wrote: > >> I keep hearing about Universal Serial Bus [USB]. Why hasn't a >> Universal Parallel Bus [UPB] been implemented yet? > > It has been done, twice. IEEE-488 for instruments, and SCSI > for small computers. > > Expensive cables made IEEE-488 a boutique item, and SCSI > (which got up to 320 MBytes/sec) was usually kinda high-end > Most Macintosh computers from 1986 to 1998 used SCSI.
Audio equipment like samplers and keyboard workstations also used SCSI, both for sample transfer between a PC and the hardware and for mass storage. Audio manufacturers were quite slow to switch from SCSI to flash memory/USB for storage/transfer; it was possible to buy new equipment with internal or external SCSI-1 ports well into the 21st century. SCSI-1 compact flash readers sell for big money on Ebay for retrofitting older equipment.
> Parallel ports DO NOT COUNT, because they aren't a bus; > the early ones weren't even bidirectional, and there was > never any good support for more than two connections. > Bus, from 'omnibus' meaning 'for everyone' implies that all > bus signals are served by all devices, not just two.
On Sat, 20 Mar 2010 17:28:11 -0700 (PDT), whit3rd <whit3rd@gmail.com> wrote:

>On Mar 20, 7:33&#2013266080;am, GreenXenon <glucege...@gmail.com> wrote: > >> I keep hearing about Universal Serial Bus [USB]. Why hasn't a >> Universal Parallel Bus [UPB] been implemented yet? > >It has been done, twice. IEEE-488 for instruments, and SCSI >for small computers. > >Expensive cables made IEEE-488 a boutique item, and SCSI >(which got up to 320 MBytes/sec) was usually kinda high-end >Most Macintosh computers from 1986 to 1998 used SCSI. > >Parallel ports DO NOT COUNT, because they aren't a bus; >the early ones weren't even bidirectional, and there was >never any good support for more than two connections.
Nonsense. You could attach anything you wanted to them. The parallel port on the PC has always been bidirectional.
>Bus, from 'omnibus' meaning 'for everyone' implies that all >bus signals are served by all devices, not just two.
ALL devices? My PCI bus doesn't serve my memory. You're just making things up now.
On Mar 20, 8:23=A0pm, "k...@att.bizzzzzzzzzzzz"
<k...@att.bizzzzzzzzzzzz> wrote:
> On Sat, 20 Mar 2010 17:28:11 -0700 (PDT), whit3rd <whit...@gmail.com> wro=
te:
> >On Mar 20, 7:33=A0am, GreenXenon <glucege...@gmail.com> wrote: > > >> I keep hearing about Universal Serial Bus [USB]. Why hasn't a > >> Universal Parallel Bus [UPB] been implemented yet? > > >It has been done, twice. =A0IEEE-488 for instruments, and SCSI > >for small computers. > > >Expensive cables made IEEE-488 a boutique item, and SCSI > >(which got up to 320 MBytes/sec) was usually kinda high-end > >Most Macintosh computers from 1986 to 1998 used SCSI. > > >Parallel ports DO NOT COUNT, because they aren't a bus; > >the early ones weren't even bidirectional, and there was > >never any good support for more than two connections. > > Nonsense. =A0You could attach anything you wanted to them. =A0The paralle=
l port on
> the PC has always been bidirectional.
Nope. http://en.wikipedia.org/wiki/Parallel_port
> > >Bus, from 'omnibus' meaning 'for everyone' implies that all > >bus signals are served by all devices, not just two. > > ALL devices? =A0My PCI bus doesn't serve my memory. =A0You're just making=
things
> up now.
So are you.
> So, how do you get faster throughput? =A0You use multiple serial lines, > like LVDS, each taking a part of the flow, and add them all togther at > the the other end.
Good point, Charlie... This is being pushed to it's extreme, with multiple Very High Speed serial busses On-Chip and Off-Chip these days. My kid is working on simulating these at IBM.. They are around 10 GHz and each serial 'bus' has adaptive transmitters and receivers so the same design can be used for a variety of signal paths without redesign.. The electronics world is getting weird :-) I got off the BUS just in time...
Tim Williams wrote:
> You're 30 years too late. They called it the Parallel Port. Used on > everything. > > Its fundamental limitations are: 1. attached to the 8MHz ISA bus (baud < > ~1Meg/s), cable length or signal quality (limited to about 1 meter), and the > cable contains 25 wires = it's a heavy bastard and requires lots of > connections = more to go wrong. > > I suppose one could make a PCI or PCI-E clocked "parallel port", maybe using > LVDS and terminated transmission lines, but then you'd be right back at > something like 100MBit ethernet (CAT5 = four parallel pairs). > > USB has only four wires. They fit nicely into a robust connector. Can't > beat that. > > Tim >
I have had NO trouble using 100 feet of cable on a parallel port (R/W too...).
whit3rd wrote:
> On Mar 20, 7:33 am, GreenXenon <glucege...@gmail.com> wrote: > >> I keep hearing about Universal Serial Bus [USB]. Why hasn't a >> Universal Parallel Bus [UPB] been implemented yet? > > It has been done, twice. IEEE-488 for instruments, and SCSI > for small computers. > > Expensive cables made IEEE-488 a boutique item, and SCSI > (which got up to 320 MBytes/sec) was usually kinda high-end > Most Macintosh computers from 1986 to 1998 used SCSI. > > Parallel ports DO NOT COUNT, because they aren't a bus; > the early ones weren't even bidirectional, and there was > never any good support for more than two connections. > Bus, from 'omnibus' meaning 'for everyone' implies that all > bus signals are served by all devices, not just two.
Well, it turns out that the ORIGINAL PC/XT in 1980 had all of the hardware on board to do full 8-bit I/O. Are you perhaps alluding to an earlier version??