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Is PCI Express not for embedded designs??

Started by Steve M September 11, 2007
We build a private label niche-market device. 
What we discovered is in extremely electronically noisy environments,
like manufacturing with welding equipment, there was only one WiFi
chipset that could handle it.
It was built by Lucent called the Hermes One. We tested every other
chipset we could find and all failed except this Lucent/Hermes combo. 

There were several companies re-branding this setup (Compaq,
Cabletron, Buffalo, Roamabout, 2Wire, Dell TrueMobile to name a just
few)

The Prisim based devices didn't work at all.(Linksys, Netgear and all
other "Small-Office / Home-Use Only" devices)

Back in the day, all you had to do was contact Lucent and ask for the
complete design specs. 
They would have you sign an NDA, then send you a 20+Meg PDF file with
everything you needed, start to finish.

All of the USB devices we've tested to date are useless toys, meant
for maybe a small office with a clear line-of-site to the AP.
My guess is low power is more important to them than Signal Strength.
They advertise 300' at 2MPS, but it's more like 30' at 1MPS.
 
These work more like BlueTooth than real, Industrial Strength WiFi. ..
:(



On Wed, 12 Sep 2007 09:45:13 -0700, Didi <dp@tgi-sci.com> wrote:

>> The main reason for going with a PCMCIA slot was up-gradability. >> This has extend the life of the product going from wired Ethernet to >> 802.11b, a,g... > >But if you do have the 802.11 knowhow you may be able to use one of >the many USB based bridges? Perhaps at least some of them would be >some device you are familiar with from the PCMCIA days, accessed over >USB? > Have you managed to use an off the shelf wifi adaptor (PCMCIA or >whatever)? If you have, I would be very interested about some details >(even if they are publically available, I still don't know where to >look, although I once spent a few hours of searching). > >Dimiter > >------------------------------------------------------ >Dimiter Popoff Transgalactic Instruments > >http://www.tgi-sci.com >------------------------------------------------------ > >On Sep 12, 7:29 pm, Steve M <i@dont_use_email.com> wrote: >> On Wed, 12 Sep 2007 10:31:16 +0200, Rene Tschaggelar <n...@none.net> >> wrote: >> >> >> >> >Steve M wrote: >> >> >> We build a small embedded device that is using a 16-Bit PCMCIA card >> >> for an Ethernet adapter. This was fine 10 years ago, but now we need >> >> to upgrade the processor/adapter and are thinking about possibly using >> >> a PCI Express based WiFi card. >> >> >> Looking through this newsgroup and Googling the web, I don't see any >> >> starting points for using an embedded micro with a single PCIe card. >> >> >> We searched out Freescale's website and no mention of libraries, >> >> design tools, Developer's Kits... nothing. >> >> >> Is the point being made that PCIe is not for "simple" embedded systems >> >> that use only one card and don't need hot-swapping or anything like >> >> that, or am I missing something here. >> >> >Yes, there are plenty of ethernet chips available >> >that can be glued to a controller without the need >> >for a PCI interface. >> >> >Rene >> >> Yes, we thought about this way back when we first developed this >> device in the 1990's >> >> The main reason for going with a PCMCIA slot was up-gradability. >> This has extend the life of the product going from wired Ethernet to >> 802.11b, a,g... >> Cost wise it's very easy to do a in-field update when all you need to >> do is pull a card and update the firmware. >> Using "off-the-shelve" hardware made maintenance easy. >> Most often, the only thing that would fail was the Ethernet Adapter >> and the end user could pick one up a the local EStore and fix it >> themselves. >> >> Sounds to me like those days are gone forever...such is progress. >
I'm beginning to think this is going to be the same as it was when we
did the 16-Bit PCMCIA card years ago.
 
First we built the prototype, got it sort-of working then received the
white papers explaining all these things we needed to do, but really
didn't need at all.

We threw the books aside, tweaked the firmware for a few days and have
been selling them ever since. 

At best from the first prototype to the working model was no more than
a week, with just two people working on it, one hardware, one
software.(Of course there have been updates through the years as we
added the new security protocols, fixed bugs and whatnot.)

99.9999% of the capabilities this new PCIe does, there is no need for
in a "simple" embedded design.

Speed is not important when you are talking to a WiFi system that
maxxes out at 27Mbps on a good day, but spends most of its life at
0-1Mbps.

Are we really going to have to add a $39.00  PLX controller chip so a
micro can talk to an $8.00 PCIe card?

I mean if the only device a micro like a Coldfire is ever going to
talk to is a WiFi card, shouldn't be able to do so on its own?

Am I over-simplifying this?














On Tue, 11 Sep 2007 16:05:16 -0700, Steve M <i@dont_use_email.com>
wrote:

>We build a small embedded device that is using a 16-Bit PCMCIA card >for an Ethernet adapter. This was fine 10 years ago, but now we need >to upgrade the processor/adapter and are thinking about possibly using >a PCI Express based WiFi card. > >Looking through this newsgroup and Googling the web, I don't see any >starting points for using an embedded micro with a single PCIe card. > >We searched out Freescale's website and no mention of libraries, >design tools, Developer's Kits&#4294967295; nothing. > >Is the point being made that PCIe is not for "simple" embedded systems >that use only one card and don't need hot-swapping or anything like >that, or am I missing something here. > > >Steve
Steve,

> Are we really going to have to add a $39.00 PLX controller chip so a > micro can talk to an $8.00 PCIe card? > > I mean if the only device a micro like a Coldfire is ever going to > talk to is a WiFi card, shouldn't be able to do so on its own? > > Am I over-simplifying this?
I do not think you are oversimplifying it, things are hardly acceptable as they are today. But there may be another option - not use PCIe at all. I have looked through a few chip(sets) which are made for single package wifi, really tiny. They are serially interfaced one way or the other - SPI in many cases, beats me why exaclty this but one can live with that. Then some of them advertise "enough power" to work without an additional amplifier, and some indicate how to connect one. I suspect the later makes the difference between those which will be good for you and the the rest (clear line of sight-style, I might prefer them as in most applications I have I would just go for the lower EMI). One of them - which can only do only "b", however - is documented and available (Thanks to Guy Macon who got the datasheet and made it available). No firmware for it to be found I know of - but stocked at Digikey... I think I found some data on another one - STM - but not everything, this may take more fights. Chances are these are compatible to something old you already know of - that Intersil thing or whatever - at this or that level. Since a PCIe board is unlikely to be easier to get documentation on than these single-package things, the choice seems easy to me. Dimiter ------------------------------------------------------ Dimiter Popoff Transgalactic Instruments http://www.tgi-sci.com ------------------------------------------------------ On Sep 13, 2:42 am, Steve M <i@dont_use_email.com> wrote:
> I'm beginning to think this is going to be the same as it was when we > did the 16-Bit PCMCIA card years ago. > > First we built the prototype, got it sort-of working then received the > white papers explaining all these things we needed to do, but really > didn't need at all. > > We threw the books aside, tweaked the firmware for a few days and have > been selling them ever since. > > At best from the first prototype to the working model was no more than > a week, with just two people working on it, one hardware, one > software.(Of course there have been updates through the years as we > added the new security protocols, fixed bugs and whatnot.) > > 99.9999% of the capabilities this new PCIe does, there is no need for > in a "simple" embedded design. > > Speed is not important when you are talking to a WiFi system that > maxxes out at 27Mbps on a good day, but spends most of its life at > 0-1Mbps. > > Are we really going to have to add a $39.00 PLX controller chip so a > micro can talk to an $8.00 PCIe card? > > I mean if the only device a micro like a Coldfire is ever going to > talk to is a WiFi card, shouldn't be able to do so on its own? > > Am I over-simplifying this? > > On Tue, 11 Sep 2007 16:05:16 -0700, Steve M <i@dont_use_email.com> > wrote: > > >We build a small embedded device that is using a 16-Bit PCMCIA card > >for an Ethernet adapter. This was fine 10 years ago, but now we need > >to upgrade the processor/adapter and are thinking about possibly using > >a PCI Express based WiFi card. > > >Looking through this newsgroup and Googling the web, I don't see any > >starting points for using an embedded micro with a single PCIe card. > > >We searched out Freescale's website and no mention of libraries, > >design tools, Developer's Kits... nothing. > > >Is the point being made that PCIe is not for "simple" embedded systems > >that use only one card and don't need hot-swapping or anything like > >that, or am I missing something here. > > >Steve