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Home > Archive > Electrical Engineering > October 2005 > EIDE Cable Specs
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| GreasyItalianAdmin 2005-09-23, 5:21 am |
| What features should one look for in the zillion or so EIDE cables/mfgs.
out there to ensure fast/reliable data transfer for DMA 66+ hard drives?
Thanks for your opinions.
| |
| NunYa Bidness 2005-09-23, 8:21 am |
| On Thu, 22 Sep 2005 20:10:42 -0700, GreasyItalianAdmin
<GreasyItalianAdmin@mafiaserver.org> Gave us:
>What features should one look for in the zillion or so EIDE cables/mfgs.
>out there to ensure fast/reliable data transfer for DMA 66+ hard drives?
>Thanks for your opinions.
DMA 66 is in the UDMA family of EIDE transfer modes.
It will function with a standard 40 pin cable or even better with
the enhanced 80 pin UDMA cable.
The master goes on the end connector. The blue connector goes into
the MOBO, and the center connector is for the slave drive.
Then, the only remaining requirement is that you plug it into a UDMA
EIDE interface connector on the motherboard or add-in card.
Features would be if they actually conformed to the color coding
spec as it relates to the connectors. Like blue for the interface
end, gray for the slave, and black on the other end for the master.
Other features these days are that they have them bundled into
"round" cables now. A bit more pricey, but yield less airflow
restriction and a bit less electrical noise.
| |
| Palindr☻me 2005-09-23, 8:21 am |
| NunYa Bidness wrote:
> On Thu, 22 Sep 2005 20:10:42 -0700, GreasyItalianAdmin
> <GreasyItalianAdmin@mafiaserver.org> Gave us:
>
>
>
>
>
> DMA 66 is in the UDMA family of EIDE transfer modes.
>
> It will function with a standard 40 pin cable or even better with
> the enhanced 80 pin UDMA cable.
>
> The master goes on the end connector. The blue connector goes into
> the MOBO, and the center connector is for the slave drive.
>
> Then, the only remaining requirement is that you plug it into a UDMA
> EIDE interface connector on the motherboard or add-in card.
>
> Features would be if they actually conformed to the color coding
> spec as it relates to the connectors. Like blue for the interface
> end, gray for the slave, and black on the other end for the master.
>
> Other features these days are that they have them bundled into
> "round" cables now. A bit more pricey, but yield less airflow
> restriction and a bit less electrical noise.
Can't add much to the above!
Size isn't everything... Most of the problems that I have
had with such cables is when they have been long ones.
Generally, getting as short as is practical seems a good idea.
The master/slave plugs are there so that you can use cable
select settings on the drive(s). If you don't use cable
select, you can stick either drive on either connector -
which sometimes makes cable routing easier.
I always like to have a drive on the end connector - even if
it is a slave drive with no master (eg a DVD on the
secondary channel). Although it seems to work ok with a
loose, unterminated, section of cable flopping around - that
offends my sensibilities - I feel that it shouldn't
work...and should have termination. You can always chop the
loose end off (scissors work a treat, if you do it
carefully, right next to the conector), I suppose.
Of course, all heading for the history books now - with SATA
drives and their ickle cables. Getting the timing good
enough between data on several parallel data channels was
always a problem and, at very high data rates, becomes
impossible without dynamic correction. Years ago, the way
was to individually match parallel data line delays using
hand-tuned stubs - BTGTTS. Yawn. Those were the days, when
hard drives lived in a re-inforced concrete holes in the
computer room floor..
--
Sue
| |
| John Gilmer 2005-09-23, 9:21 am |
|
>
> Other features these days are that they have them bundled into
> "round" cables now. A bit more pricey, but yield less airflow
> restriction and a bit less electrical noise.
I have always had mixed "emotions" over those flat cables.
I first say them used in the old DEC computers. My first impression is
that is seemed SLOPPY! But when I think about it and realize that every
other wire is a virtual ground (usually) I have come around to thinking that
I would be hard pressed to come up with a "round" cable that I could
guarantee would work as well or better.
| |
|
| In article <4333e52c$0$9217@dingus.crosslink.net>, gilmer@crosslink.net
says...
>
>
>
> I have always had mixed "emotions" over those flat cables.
>
> I first say them used in the old DEC computers. My first impression is
> that is seemed SLOPPY! But when I think about it and realize that every
> other wire is a virtual ground (usually) I have come around to thinking that
> I would be hard pressed to come up with a "round" cable that I could
> guarantee would work as well or better.
>
I did a lot of work with the IDC cables many years back. As long as
every-other pin is ground, they're quite good, electrically. IDE
cables don't have enough grounds though and are rather poor (but good
'nuff). The 80-conductor cables are better, but still not enough
ground pins to make a great transmission environment. Although again,
good enough for the application.
OTOH, I've been using round IDE/ATA cables because they make routing
the cables so much easier. I haven't studied their properties, though
they too work "good enough".
--
Keith
| |
| gfretwell@aol.com 2005-09-23, 1:21 pm |
| On Thu, 22 Sep 2005 20:10:42 -0700, GreasyItalianAdmin
<GreasyItalianAdmin@mafiaserver.org> wrote:
>What features should one look for in the zillion or so EIDE cables/mfgs.
>out there to ensure fast/reliable data transfer for DMA 66+ hard drives?
>Thanks for your opinions.
I have some 6' braided cables (4 ½' longer than the spec) and they
work fine on DMA66 drives. This is really a pretty robust interface if
you have good cables.
| |
| GreasyItalianAdmin 2005-09-23, 6:21 pm |
| GreasyItalianAdmin <GreasyItalianAdmin@mafiaserver.org> wrote in
news:dgvrnk$u5t$1@domitilla.aioe.org:
> What features should one look for in the zillion or so EIDE
> cables/mfgs. out there to ensure fast/reliable data transfer for DMA
> 66+ hard drives? Thanks for your opinions.
Thanks to all the good responses.
Quickly reading the replies, maybe I was not clear. What I was wondering
specifically is what type of construction is best to eliminate errors?
Some of the companies advertise various shielding materials and being
ignorant in this area, I was wondering what construction materials are
best and how do I separate the cheaply made stuff from the good stuff?
The regular flat ribbon cables in the machine presently (40 wire, I
think) are all twisted up and I think some of the sharp bends were
giving me multibit errors-I tried to restraighten them and the multibit
errors went away. Also I have read from some articles on the net that
the round cables do not conform to the ATA standards? Also suprised to
hear from one poster that he used such a long cable, everything I've
read says no more than 18 inches.
| |
| NunYa Bidness 2005-09-23, 8:21 pm |
| On Fri, 23 Sep 2005 12:08:49 +0100, Palindr?me
<sb382638@hotmail.com.invalid> Gave us:
>The master/slave plugs are there so that you can use cable
>select settings on the drive(s). If you don't use cable
>select, you can stick either drive on either connector -
>which sometimes makes cable routing easier.
Interesting. I thought it was an issue surrounding the fact that
the "controller" actually resides on the hard drive chosen as master,
and its location of the "bus" the cable offers.
All these years that we have been actually selecting the drive
assignment, when we could have been placing the selector on csel the
whole time.
Query though: When one makes both drives set to cable select, the
cable position determines the master?
Is that how I read it? Thanks.
| |
| NunYa Bidness 2005-09-23, 8:21 pm |
| On Fri, 23 Sep 2005 07:16:07 -0400, "John Gilmer"
<gilmer@crosslink.net> Gave us:
>
>
>
>I have always had mixed "emotions" over those flat cables.
>
>I first say them used in the old DEC computers. My first impression is
>that is seemed SLOPPY! But when I think about it and realize that every
>other wire is a virtual ground (usually) I have come around to thinking that
>I would be hard pressed to come up with a "round" cable that I could
>guarantee would work as well or better.
>
IIRC those rounded versions are ribbons that have been tucked into a
tube. I do not know how a 40 or 80 strand round configuration
conductor (shirt of twisted pair configurations) could work at the
data rates given for the differentially de-coupled "noise free" ribbon
cables.
| |
| NunYa Bidness 2005-09-23, 8:21 pm |
| On Fri, 23 Sep 2005 10:36:51 -0400, krw <krw@att.biz> Gave us:
>In article <4333e52c$0$9217@dingus.crosslink.net>, gilmer@crosslink.net
>says...
>I did a lot of work with the IDC cables many years back. As long as
>every-other pin is ground, they're quite good, electrically.
That rules ALL 40 pin cables out.
> IDE
>cables don't have enough grounds though and are rather poor (but good
>'nuff).
They only have one at the 40 pin level.
> The 80-conductor cables are better, but still not enough
>ground pins to make a great transmission environment.
Huh? Try every other conductor.
> Although again,
>good enough for the application.
Most assuredly, since it DOES "have enough grounds".
>
>OTOH, I've been using round IDE/ATA cables because they make routing
>the cables so much easier. I haven't studied their properties, though
>they too work "good enough".
A simple test is to run a hard drive throughput benchmark with a 40,
80, and round cable configuration, log the results, and examine the
log.
| |
| NunYa Bidness 2005-09-23, 8:21 pm |
| On Fri, 23 Sep 2005 11:31:16 -0400, gfretwell@aol.com Gave us:
>On Thu, 22 Sep 2005 20:10:42 -0700, GreasyItalianAdmin
><GreasyItalianAdmin@mafiaserver.org> wrote:
>
>
>I have some 6' braided cables (4 ½' longer than the spec) and they
>work fine on DMA66 drives. This is really a pretty robust interface if
>you have good cables.
Braided? Wouldn't that be "twisted pairs"? Speaker wires got
braided, but ribbon cables get twisted pair configurations.
The new step these days are differential pairing.
| |
| NunYa Bidness 2005-09-23, 9:21 pm |
| On Fri, 23 Sep 2005 20:50:42 +0000 (UTC), GreasyItalianAdmin
<GreasyItalianAdmin@mafiaserver.org> Gave us:
>GreasyItalianAdmin <GreasyItalianAdmin@mafiaserver.org> wrote in
>news:dgvrnk$u5t$1@domitilla.aioe.org:
>
>
>Thanks to all the good responses.
>Quickly reading the replies, maybe I was not clear. What I was wondering
>specifically is what type of construction is best to eliminate errors?
>Some of the companies advertise various shielding materials and being
>ignorant in this area, I was wondering what construction materials are
>best and how do I separate the cheaply made stuff from the good stuff?
>The regular flat ribbon cables in the machine presently (40 wire, I
>think) are all twisted up and I think some of the sharp bends were
>giving me multibit errors-I tried to restraighten them and the multibit
>errors went away. Also I have read from some articles on the net that
>the round cables do not conform to the ATA standards? Also suprised to
>hear from one poster that he used such a long cable, everything I've
>read says no more than 18 inches.
I noticed that the 6 foot spec he mentioned I have not seen
elsewhere. Maybe for the old IDE spec, but UDMA certainly has very
short limits.
IF your motherboard supports UDMA 66 then you should replace all of
your 40 pin cabling with 80 pin UDMA cables. They will both eliminate
the errors, and allow the auto sensed speed capacity to get jacked up.
Your problems will disappear!
| |
| Palindr☻me 2005-09-23, 9:21 pm |
| NunYa Bidness wrote:
> On Fri, 23 Sep 2005 12:08:49 +0100, Palindr?me
> <sb382638@hotmail.com.invalid> Gave us:
>
>
>
>
> Interesting. I thought it was an issue surrounding the fact that
> the "controller" actually resides on the hard drive chosen as master,
> and its location of the "bus" the cable offers.
>
> All these years that we have been actually selecting the drive
> assignment, when we could have been placing the selector on csel the
> whole time.
>
> Query though: When one makes both drives set to cable select, the
> cable position determines the master?
>
> Is that how I read it? Thanks.
Most of the original 40 conductor cables are a straight bus
- all pins connected. A very few were wired for cable select
- but most were not. Hence the need to set master and slave
on the drives - unless you knew you had one of these
"special" cables. ISTR that IBM used them but few other OEM did.
Most (all) of the 80 conductor cables are configured for
cable select and pin 28 is not connected on the slave
connector on the cable. Thus a cable select drive plugged
onto that socket will always act as a slave. But this can be
over-ridden by the master slave jumpers on the drive. The
master connector on the cable has pin 28 connected and would
always set a cable select drive connected to it as master.
Again, it can be over-ridden by drive jumpers.
Yep, generally, if you have a 40 cable, you have to set the
drives. If you have an 80 cable, you can just use cable
select. I personally only use cable select these days as I
am always swapping drives hither and thither and have
replaced all my 40's with 80's.
http://www.pcguide.com/ref/hdd/if/i...fCable80-c.html
http://www.pcguide.com/ref/hdd/if/ide/conf_CS.htm
HTH
Sue
| |
| Palindr☻me 2005-09-23, 9:21 pm |
| NunYa Bidness wrote:
> On Fri, 23 Sep 2005 07:16:07 -0400, "John Gilmer"
> <gilmer@crosslink.net> Gave us:
>
>
>
> IIRC those rounded versions are ribbons that have been tucked into a
> tube. I do not know how a 40 or 80 strand round configuration
> conductor (shirt of twisted pair configurations) could work at the
> data rates given for the differentially de-coupled "noise free" ribbon
> cables.
Most of the cheap rounded versions simply have flat cable
twisted up so it will fit in a sleeve. I have some
(expensive) true round cable where the core layout has been
worked out very carefully so each active core is adjacent to
earth cores and not another data core, both wrt the ring
layer the core is in and the adjacent ring layers. You can
find details of these cables on the web, but it is half past
midnight so I hope you will forgive me for not going looking
for you. ;)
--
Sue
| |
| Palindr☻me 2005-09-23, 9:21 pm |
| NunYa Bidness wrote:
> On Fri, 23 Sep 2005 10:36:51 -0400, krw <krw@att.biz> Gave us:
>
>
>
>
> That rules ALL 40 pin cables out.
>
>
>
>
> They only have one at the 40 pin level.
>
>
>
>
> Huh? Try every other conductor.
>
>
>
>
> Most assuredly, since it DOES "have enough grounds".
>
>
>
> A simple test is to run a hard drive throughput benchmark with a 40,
> 80, and round cable configuration, log the results, and examine the
> log.
I did something similar to this - starting with a looong
cable and moving the end connector along, 1" at a time, and
chopping off the stub, until the error rate flattened out.
It varied greatly between makes and models of computers.
On one particular Dell machine, anything longer than 7"
was a total no-no. Of course, 7" should be long enough for
anyone..;)
--
Sue
| |
| Palindr☻me 2005-09-23, 9:21 pm |
| NunYa Bidness wrote:
> On Fri, 23 Sep 2005 11:31:16 -0400, gfretwell@aol.com Gave us:
>=20
>=20
s.=20[color=darkred]
s?[color=darkred]
[color=darkred]
>=20
>=20
> Braided? Wouldn't that be "twisted pairs"? Speaker wires got
> braided, but ribbon cables get twisted pair configurations.
>=20
> The new step these days are differential pairing.
I suspect that he meant a braided sheath.
--
Sue
| |
| Palindr☻me 2005-09-23, 9:21 pm |
| NunYa Bidness wrote:
> On Fri, 23 Sep 2005 20:50:42 +0000 (UTC), GreasyItalianAdmin
> <GreasyItalianAdmin@mafiaserver.org> Gave us:
>
>
>
>
> I noticed that the 6 foot spec he mentioned I have not seen
> elsewhere. Maybe for the old IDE spec, but UDMA certainly has very
> short limits.
>
> IF your motherboard supports UDMA 66 then you should replace all of
> your 40 pin cabling with 80 pin UDMA cables. They will both eliminate
> the errors, and allow the auto sensed speed capacity to get jacked up.
>
> Your problems will disappear!
I did that and yet my garden still floods every Winter... ;)
--
Sue
| |
| NunYa Bidness 2005-09-23, 9:21 pm |
| On Sat, 24 Sep 2005 00:42:44 +0100, Palindr?me
<sb382638@hotmail.com.invalid> Gave us:
>NunYa Bidness wrote:
>
>
>I did that and yet my garden still floods every Winter... ;)
Yet you still make me desire your companionship for... ever!
I love girls that are smarter than I am. That is also why I have
been lonely for decades too!
| |
| Palindr☻me 2005-09-23, 9:21 pm |
| NunYa Bidness wrote:
> On Sat, 24 Sep 2005 00:42:44 +0100, Palindr?me
> <sb382638@hotmail.com.invalid> Gave us:
>
>
>
>
> Yet you still make me desire your companionship for... ever!
>
> I love girls that are smarter than I am. That is also why I have
> been lonely for decades too!
LOL, I dunno why, as soon as I mention what I do to IDE
cables that are too long to work reliably, any bf I have had
has turned pale and remembered an important previous
engagement...;) - never to be seen again.
--
Sue
| |
| gfretwell@aol.com 2005-09-23, 10:21 pm |
| On Fri, 23 Sep 2005 23:14:26 GMT, NunYa Bidness
<nunyabidness@nunyabidness.org> wrote:
> Braided? Wouldn't that be "twisted pairs"? Speaker wires got
>braided, but ribbon cables get twisted pair configurations.
Yup they do act like twisted pairs. These were originally used on IBM
3480 tape drives but they had the same connector so I tried them.
Originally I used them on a CD drive but later I put an external hard
drive out there. This is on my MP3 player machine out in the pool bar,
the system unit is in the garage. Cables go through a hole in the
wall.
| |
| gfretwell@aol.com 2005-09-23, 10:21 pm |
| On Sat, 24 Sep 2005 00:41:39 +0100, Palindr?me
<sb382638@hotmail.com.invalid> wrote:
>I suspect that he meant a braided sheath.
Nope, grounds are braided into the signal cables. They also use bigger
wire than a usual IDE
| |
| NunYa Bidness 2005-09-23, 11:21 pm |
| On Sat, 24 Sep 2005 01:08:43 +0100, Palindr?me
<sb382638@hotmail.com.invalid> Gave us:
>NunYa Bidness wrote:
>
>
>LOL, I dunno why, as soon as I mention what I do to IDE
>cables that are too long to work reliably, any bf I have had
>has turned pale and remembered an important previous
>engagement...;) - never to be seen again.
I've been on the noise abatement crew for a LONG time.
My last supply was 20mV noise on a 1500 Volt 250 W line for a CAT
scanner. That's a pretty tight supply. Less than one volt swing from
no load to full load. Very tight. Noise was a major problem.
Initially, we made a + and - 60 Volt DC supply to feed the main supply
rails.
It had too much line noise passing through it to the outputs. Even
with a toroid main transformer. We changed to two of our off the
shelf 60 Volt switchers. The noise was abated, and a bit more cooling
capacity was added.
| |
|
| In article <bn29j15gced0t36gpbbdpqh3tmhldllp7k@4ax.com>,
nunyabidness@nunyabidness.org says...
> On Fri, 23 Sep 2005 10:36:51 -0400, krw <krw@att.biz> Gave us:
>
>
> That rules ALL 40 pin cables out.
Not if there are 20 signals and 20 grounds. Note that I said IDC
cables. I did *not* say IDE cables.
>
> They only have one at the 40 pin level.
Not according to my information. Pins 2, 19, 22, 24, 26, 30, and 40
are ground. Note that there is a ground next to the strobes (23 =
/IOW, 25 = /IOR, 31 = IRQ).
>
> Huh? Try every other conductor.
I said "pins", not conductors.
>
> Most assuredly, since it DOES "have enough grounds".
No, it really doesn't for a good transmission environment. More ground
*PINS* are needed. It's "good enough" for IDE, since there are few
signals that are really important (data and address lines are allowed
to settle before being qualified by a strobe).
>
> A simple test is to run a hard drive throughput benchmark with a 40,
> 80, and round cable configuration, log the results, and examine the
> log.
I prefer to look at signals with a scope to see how good the interface
is. A TDR on the cable is also useful.
--
Keith
| |
| NunYa Bidness 2005-09-26, 6:21 pm |
| On Mon, 26 Sep 2005 10:28:53 -0400, krw <krw@att.biz> Gave us:
>
>Not if there are 20 signals and 20 grounds. Note that I said IDC
>cables. I did *not* say IDE cables.
Even those would be dependent on how the PCB layout person laid out
the board. He may not have used it that way. it wasn't required in
any sense. Differential pairs weren't in wide practice (in the PC
realm anyway) until recently with EIDE. It has been around a while in
SCSI, and known about in parallel conductor data pass design for a
long time. They have allowed for higher speed signaling without
reflections or crosstalk over longer passes. That's cool. Speed is
good. :-]
You are right though, configured the way you bespeak.
Maybe we can have those new vertically oriented (magnetically) hard
drives at 2.5" form factor or such, and have an array of them, all hot
swappable on SATA passes, and have a huge parallel set of SATA
conductors, all segregated from each other that way.
A person could wear a belt that has a fault tolerant, one terabyte
RAID file server on it, field repairable, connected to a battery, and
backpack laptop. Everyone could wear a live video recorder!
| |
| NunYa Bidness 2005-09-26, 6:21 pm |
| On Mon, 26 Sep 2005 10:28:53 -0400, krw <krw@att.biz> Gave us:
>
>I said "pins", not conductors.
Yes, but I said conductors, as we are talking about successive
parallel conductors on a ribbon, before the header attachment. That
is where the noise cancellation takes place.
| |
| keith 2005-09-27, 12:21 am |
| On Mon, 26 Sep 2005 21:11:37 +0000, NunYa Bidness wrote:
> On Mon, 26 Sep 2005 10:28:53 -0400, krw <krw@att.biz> Gave us:
>
>
> Even those would be dependent on how the PCB layout person laid out
> the board.
One doesn't just lett the PCB layout person do anything he wants! There
are guidelines, groundrules, and quick-kicks to the butt!
> He may not have used it that way. it wasn't required in
> any sense.
It was on any work *I* did, whether I specified the transmission
interfaces or designed the entire system! The layout guy never did
anything outside the spec. Good grief! How do you think things are done?
> Differential pairs weren't in wide practice (in the PC
> realm anyway) until recently with EIDE.
The PC is hardly the end-all. ...and EIDE *still* doesn't use differntial
pairs. BTW, who was talking about differential pairs?
> It has been around a while in
> SCSI, and known about in parallel conductor data pass design for a long
> time. They have allowed for higher speed signaling without reflections
> or crosstalk over longer passes. That's cool. Speed is good. :-]
Sure, but much SCSI wasn't differential either. Better than IDE, but not
all differential.
> You are right though, configured the way you bespeak.
I know. ;-) I did several interfaces with 50-pin IDC cables with
10 connectors spaced at .75". The quality of the transmission environment
really surprised me, but was a little low (80ish ohms, rather than about
110 for long cables, IIRC).
> Maybe we can have those new vertically oriented (magnetically) hard
> drives at 2.5" form factor or such, and have an array of them, all hot
> swappable on SATA passes, and have a huge parallel set of SATA
> conductors, all segregated from each other that way.
Why?
BTW, I'm less than impressed by SATA. There is little gain. If only
they'd packaged the power in with the signal cable...
> A person could wear a belt that has a fault tolerant, one terabyte
> RAID file server on it, field repairable, connected to a battery, and
> backpack laptop. Everyone could wear a live video recorder!
Why? I'm happy with a couple of sub gigabyte USB sticks on my keychain.
....then again, I'm not much into video (radio on a stick, OTOH... ;-).
--
Keith
| |
| keith 2005-09-27, 12:21 am |
| On Mon, 26 Sep 2005 21:13:40 +0000, NunYa Bidness wrote:
> On Mon, 26 Sep 2005 10:28:53 -0400, krw <krw@att.biz> Gave us:
>
>
> Yes, but I said conductors, as we are talking about successive
> parallel conductors on a ribbon, before the header attachment. That
> is where the noise cancellation takes place.
Wrong. Without PINS to carry those ground currents, most of the benefit
of the ground conductors is lost. Inductance, Luke.
--
Keith
| |
| NunYa Bidness 2005-09-27, 8:21 am |
| On Mon, 26 Sep 2005 22:57:10 -0400, keith <krw@att.bizzzz> Gave us:
>The PC is hardly the end-all. ...and EIDE *still* doesn't use differntial
>pairs. BTW, who was talking about differential pairs?
UDMA cables are differentially paired lines.
| |
| NunYa Bidness 2005-09-27, 8:21 am |
| On Mon, 26 Sep 2005 22:57:10 -0400, keith <krw@att.bizzzz> Gave us:
>Why? I'm happy with a couple of sub gigabyte USB sticks on my keychain.
>...then again, I'm not much into video (radio on a stick, OTOH... ;-).
You are talking about simple portable storage. Way too slow. I was
talking about live video recording, and battle field local theater
communications recording, as well as data and files, etc.
I am talking about wearable computers.
| |
| NunYa Bidness 2005-09-27, 8:21 am |
| On Mon, 26 Sep 2005 22:58:34 -0400, keith <krw@att.bizzzz> Gave us:
>On Mon, 26 Sep 2005 21:13:40 +0000, NunYa Bidness wrote:
>
>
>Wrong. Without PINS to carry those ground currents, most of the benefit
>of the ground conductors is lost. Inductance, Luke.
If every other pin IS grounded as we were talking about. of course
it takes place via the header pins. Once connected, however, the
crosstalk noise is canceled.
| |
| Palindr☻me 2005-09-27, 9:21 am |
| NunYa Bidness wrote:
> On Mon, 26 Sep 2005 22:57:10 -0400, keith <krw@att.bizzzz> Gave us:
>
>
>
>
> UDMA cables are differentially paired lines.
This is the pinout of the connector for a UDMA cable, the other cores
being connected to ground. Data is passed Single-Ended,via data line and
ground. The "Ultra" aspect is that both edges of the strobe signal is
used to transfer data, rather than the rising edge only (as used
previously).
1 Reset 2 Ground
3 Data 7 4 Data 8
5 Data 6 6 Data 9
7 Data 5 8 Data 10
9 Data 4 10 Data 11
11 Data 3 12 Data 12
13 Data 2 14 Data 13
15 Data 1 16 Data 14
17 Data 0 18 Data 15
19 Ground 20 Key
21 DMARQ 22 Ground
23 DIOW- 24 Ground
25 DIOR- 26 Ground
27 IORDY 28 CSEL
29 DMARK- 30 Ground
31 INTRQ 32 IOCS16-
33 DA1 34 PDIAG-
35 DA0 36 DA2
37 CS1FX- 38 CS3FX-
39 DASP- 40 Ground
--
Sue
| |
|
| In article <sb9ij1l9lot1p97ajnljdpsfk2mc7oa9lg@4ax.com>,
nunyabidness@nunyabidness.org says...
> On Mon, 26 Sep 2005 22:57:10 -0400, keith <krw@att.bizzzz> Gave us:
>
>
> UDMA cables are differentially paired lines.
>
No they are most certainly not differential! They are paired with
grounds.
--
Keith
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|
| In article <8e9ij1tbonrtathjd67us1f0nolcs1igf0@4ax.com>,
nunyabidness@nunyabidness.org says...
> On Mon, 26 Sep 2005 22:57:10 -0400, keith <krw@att.bizzzz> Gave us:
>
>
> You are talking about simple portable storage. Way too slow. I was
> talking about live video recording, and battle field local theater
> communications recording, as well as data and files, etc.
Ok. As I said, I have *NO* use for video. If I did, I'd want an RF
link to the recorder. I certainly don't want to carry it.
> I am talking about wearable computers.
Ick!
--
Keith
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|
| In article <ii9ij1dol3sg48ml0770p6mgu8jtdr6nan@4ax.com>,
nunyabidness@nunyabidness.org says...
> On Mon, 26 Sep 2005 22:58:34 -0400, keith <krw@att.bizzzz> Gave us:
>
>
> If every other pin IS grounded as we were talking about. of course
> it takes place via the header pins. Once connected, however, the
> crosstalk noise is canceled.
>
Nope. Think again. Where are the currents flowing?
--
Keith
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| Aratzio 2005-09-27, 11:21 am |
| On Tue, 27 Sep 2005 11:02:13 GMT, NunYa Bidness
<nunyabidness@nunyabidness.org> transparently proposed:
>On Mon, 26 Sep 2005 22:58:34 -0400, keith <krw@att.bizzzz> Gave us:
>
>
> If every other pin IS grounded as we were talking about. of course
>it takes place via the header pins. Once connected, however, the
>crosstalk noise is canceled.
Just wanted to drop by and say "Hi, Spunky! What up, Dog?".
PS: Not canceled just reduced to manageable/negligible levels.
--
Pierre Salinger Hook, Line & Sinker - May, 2005
Hammer of Thor - July, 2005
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| Aratzio 2005-09-27, 11:21 am |
| On Tue, 27 Sep 2005 11:00:30 GMT, NunYa Bidness
<nunyabidness@nunyabidness.org> transparently proposed:
>
> I am talking about wearable computers.
Hey, Furby, ya ever thought about shoving one up that massive anal
oriface of yours and wearing it there?
--
Pierre Salinger Hook, Line & Sinker - May, 2005
Hammer of Thor - July, 2005
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| Aratzio 2005-09-27, 11:21 am |
| On Sat, 24 Sep 2005 00:00:05 GMT, NunYa Bidness
<nunyabidness@nunyabidness.org> transparently proposed:
<sneck>
>
> Yet you still make me desire your companionship for... ever!
>
> I love girls that are smarter than I am. That is also why I have
>been lonely for decades too!
No, it is because you are a fucknozzle. Try this, go out someplace
there are women. Try your pathetic pick up line on them. When they
stop laughing and begin bitchslapping your XXX, you may, just might,
possiblity get the clue driven into your ugly noggin.
HTH
'Ratz
--
Pierre Salinger Hook, Line & Sinker - May, 2005
Hammer of Thor - July, 2005
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| VWWall 2005-09-27, 12:21 pm |
| Palindr☻me wrote:
> NunYa Bidness wrote:
>
There are two specs for ATA cables. One has even numbered grounded
conductors, the other uses odd numbered grounded conductors as shields.
Neither is "differentially paired".
[color=darkred]
> This is the pinout of the connector for a UDMA cable, the other cores
> being connected to ground. Data is passed Single-Ended,via data line and
> ground. The "Ultra" aspect is that both edges of the strobe signal is
> used to transfer data, rather than the rising edge only (as used
> previously).
>
> 1 Reset 2 Ground
> 3 Data 7 4 Data 8
> 5 Data 6 6 Data 9
> 7 Data 5 8 Data 10
> 9 Data 4 10 Data 11
> 11 Data 3 12 Data 12
> 13 Data 2 14 Data 13
> 15 Data 1 16 Data 14
> 17 Data 0 18 Data 15
> 19 Ground 20 Key
> 21 DMARQ 22 Ground
> 23 DIOW- 24 Ground
> 25 DIOR- 26 Ground
> 27 IORDY 28 CSEL
> 29 DMARK- 30 Ground
> 31 INTRQ 32 IOCS16-
> 33 DA1 34 PDIAG-
> 35 DA0 36 DA2
> 37 CS1FX- 38 CS3FX-
> 39 DASP- 40 Ground
One small correction: Pin #34 is now called PDIAG-CBLID. It is used to
identify 80 conductor cables at the MB. This is why you see the "cut"
in the conductor attached to Pin #34 at the mother board. It still
serves as PDIAG between the two drives.
This is why my answer to using ATA cables with other than the intended
connector positions is always "it depends". One nice things about
standards is-- they are not "standard".
--
Virg Wall, P.E.
| |
|
| In article <91d_e.37$4h2.7@newsread3.news.pas.earthlink.net>,
vwall@DEADearthlink.net says...
> This is why my answer to using ATA cables with other than the intended
> connector positions is always "it depends". One nice things about
> standards is-- they are not "standard".
>
That's the nice thing about standards; there are *so* many to choose
from. ;-)
--
Keith
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| NunYa Bidness 2005-09-27, 9:21 pm |
| On Tue, 27 Sep 2005 12:45:03 +0100, Palindr?me
<sb382638@hotmail.com.invalid> Gave us:
>NunYa Bidness wrote:
>
>This is the pinout of the connector for a UDMA cable, the other cores
>being connected to ground. Data is passed Single-Ended,via data line and
>ground. The "Ultra" aspect is that both edges of the strobe signal is
>used to transfer data, rather than the rising edge only (as used
>previously).
>
>1 Reset 2 Ground
>3 Data 7 4 Data 8
>5 Data 6 6 Data 9
>7 Data 5 8 Data 10
>9 Data 4 10 Data 11
>11 Data 3 12 Data 12
>13 Data 2 14 Data 13
>15 Data 1 16 Data 14
>17 Data 0 18 Data 15
>19 Ground 20 Key
>21 DMARQ 22 Ground
>23 DIOW- 24 Ground
>25 DIOR- 26 Ground
>27 IORDY 28 CSEL
>29 DMARK- 30 Ground
>31 INTRQ 32 IOCS16-
>33 DA1 34 PDIAG-
>35 DA0 36 DA2
>37 CS1FX- 38 CS3FX-
>39 DASP- 40 Ground
And the other 40 lines are?
| |
| NunYa Bidness 2005-09-27, 9:21 pm |
| On Tue, 27 Sep 2005 09:39:07 -0400, krw <krw@att.biz> Gave us:
>In article <sb9ij1l9lot1p97ajnljdpsfk2mc7oa9lg@4ax.com>,
>nunyabidness@nunyabidness.org says...
>No they are most certainly not differential! They are paired with
>grounds.
That's what I am talking about.
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| Palindr☻me 2005-09-28, 4:21 am |
| NunYa Bidness wrote:
> On Tue, 27 Sep 2005 12:45:03 +0100, Palindr?me
> <sb382638@hotmail.com.invalid> Gave us:
>
>
>
>
> And the other 40 lines are?
Erm, what "other 40 lines"?
Perhaps you could re-read what I wrote?
--
Sue
| |
|
| In article <p7njj11vu28j8nmv18hoj5rhh6bshsmlob@4ax.com>,
nunyabidness@nunyabidness.org says...
> On Tue, 27 Sep 2005 09:39:07 -0400, krw <krw@att.biz> Gave us:
>
>
> That's what I am talking about.
>
That is *NOT* differential.
--
Keith
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| NunYa Bidness 2005-09-28, 8:21 pm |
| On Wed, 28 Sep 2005 07:52:46 +0100, Palindr?me
<sb382638@hotmail.com.invalid> Gave us:
>NunYa Bidness wrote:
>
>Erm, what "other 40 lines"?
>
>Perhaps you could re-read what I wrote?
UDMA cables, which is what you declared at the beginning of the
list, have 80 conductors, even though the header only has 40. What
are the other 40 connected to?
I just used the wrong term. I didn't mean to throw anyone off, I'm
confused enough myself... ;-]
| |
| NunYa Bidness 2005-09-28, 10:21 pm |
| On Thu, 29 Sep 2005 00:16:52 +0100, Palindr?me
<sb382638@hotmail.com.invalid> Gave us:
>
>Yep, "differential pair" does have a very particular meaning
> and to anyone in that trade, getting it wrong is
>tantamount to calling the Scots, English.. ;o)
Bob's yer uncle!
| |
| Aratzio 2005-09-29, 12:21 am |
| On Wed, 28 Sep 2005 22:35:35 GMT, NunYa Bidness
<nunyabidness@nunyabidness.org> got double secret probation because:
> I just used the wrong term. I didn't mean to throw anyone off, I'm
>confused enough myself... ;-]
No, you are a faux injuneer playing at the real thing, seaman.
--
Pierre Salinger Hook, Line & Sinker - May, 2005
Hammer of Thor - July, 2005
| |
| Michael A. Terrell 2005-10-24, 3:21 am |
| gfretwell@aol.com wrote:
>
> Yup they do act like twisted pairs. These were originally used on IBM
> 3480 tape drives but they had the same connector so I tried them.
> Originally I used them on a CD drive but later I put an external hard
> drive out there. This is on my MP3 player machine out in the pool bar,
> the system unit is in the garage. Cables go through a hole in the
> wall.
Are you talking about those black and yellow twisted pair IBM
cables? I don't know how many truck loads of those we recycled in one
year. We couldn't even give them away.
--
?
Michael A. Terrell
Central Florida
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