Mezzanine Buses

There are a great many Mezzanine buses, some more out-dated than others. Mezzanine cards are small form factor boards that reside as a daughter card on a VME or cPCI mother-board to name a few interfaces. Mezzanine cards to not directly interface to the main system backplane as does VME for example. Most of the Mezzanine interface on this site are represented by two separate pages; one page carries the particular board manufacturers and another page covers the description of the electrical interface and mechanical form factor.

The oldest of the current Mezzanine board formats on the market is the IP Card or Industry Pack I/O Modules. Basically a non-intelligent board format used in a number of systems, a bit dated at this point in time, but there are still Companies Producing IP Modules. Page views are almost down to zero for this board format, which seems odd as it was an I/O based module.

The M-Module which is just as old still receives a few page views, but there doesn't appear to be much support in Producing M-Module Cards.

The mezzanine board format that replaced the IP board was the PMC format, or PCI Mezzanine Card. The PMC board added a controller but still allowed for any required I/O, previously handled by the IP card. So there are still many Companies Producing PMC Boards. A variant of the PMC interface is the PMC-X format. Both of these board standards used the PCI bus as the electrical interface, so really they are somewhat out dated [PCI Card Manufacturers].

The follow-on to the PMC standard was the PPMC interface, or Processor PMC format. There are a few companies that Produce PPMC Boards which were true processor based cards, on a PCI bus. Another related was board format is the PTMC Interface, or Telcom PMC standard [still using the PCI electrical interface].

These are all open standards so the board specifications could be used on any carrier card, but some interfaces were designed specifically for the VME bus, others for the cPCI Interface, and still others for the AdvancedTCA Interface. The AMC Mezzanine card was designed to interface to the new ATCA standard, being relatively new there is a small but growing number of Companies Producing AMC Boards.

Additional mezzanine boards include FMC,  and XMC standards.

Proprietary Embedded Board Formats

I just happened to be checking a few of the COTS Board Manufacturer pages today. I noticed that the few pages I picked to update, at random, were receiving almost no incoming visits. It only took a few minutes before I realized that the three board formats I had updated were all proprietary standards. Really proprietary board formats, because I don't know that any board standard was ever released ~ other than a detailed data sheet so the board could be designed into an embedded system.

So I opened the STX Board Format page to do a routine update, or just to check to see it was up-to-date. Anyway I also opened site analytics to see how the page was doing for visits. That  board format receives almost no visitors, then I started to wonder why that was. That's when I noticed that the format was proprietary in nature.

There really is no reason for someone to visit my site for a board format that is only produced by one or two individual companies, unless they don't realize the standard is proprietary. So I can understand why the incoming visits to that page are so low. However; on the positive side, by listing the standard on the site the information is there to review if it ever comes up in conversation. That is, I don't have to claim ignorance, within minutes I know what the STX board is just by pulling up the page.

I figured I would then check a few other proprietary board standards, like E2Brain. Same story with this industrial format, except that this page received even lower page views by 30%. I pulled up the PISA board standard next. Now to my surprise the PISA format was getting 3x the page views even though I figured this format was obsolete. The PISA slot format is based on a modified PCAT slot connector, which by definition implies obsolesce because the industry moved onto PCI many years ago.

I don't have a point here, other then to indicate that some pages will never do well on the web, but they still deserve a place on interfacebus to insure the topic is covered; Industrial Embedded Board Formats.
I did make sure that the page clearly indicated that the board formats were proprietary......

Graphic; Single Board Computer [SBC]. Public Domain.

PCI-104 Form Factor

Following along a previous posting about the slow adoption of new interface bus standards, I have yet another one. Upgrading the page that covers PC104 board manufacturers and separating out vendors that produce only PCI104 cards, I don't find that many companies producing PCI/104 boards.

The attached graphic shows the road-map [up-grade path]. The PC104 standard started out with an IBM XT bus interface in a 90mm x 96mm board format in 1992. Following that release, the IBM AT bus interface was added a few years later. Then in 1997 the PCI bus interface was added to reside along side the PCAT bus, as a new connector. With each upgrade board area was reduced because of the increase in the number of connectors. However; card-to-card transmission speed increased as the interface buses increased their throughput.

The PCI104 specification was released in 2003. The change here was to leave the PCI interface, now common, and remove the connectors and interfaces dedicated to the out-dated PCAT bus which than freed up board space.

Odd that there are still not that many PCI/104 board vendors. The stack height is reduced form 6 cards to 4 cards, but they may still be stacked using the PCI104 standard. Could it be that the CPU card is the only CCA that requires a PCI interface, while all the other I/O cards don't benefit from being redesigned? Maybe the increased density of FPGAs compensated for the reduced board area? Perhaps most OEMs require a 6-card stack in a PC/104 chassis. What ever the reason, the original PC bus lives on......

Graphic; The different connector locations for each PC/104 board format.

CableCARD

CableCARD from what I have found so far is a 16-bit PC Card in a PCMCIA format. CableCARD was designed to replace the cable box from the cable company; any company could produce a CableCARD from the standard so you were not locked into renting from the cable company. This was a government thing, I guess the FCC.

CableCARD appears as a PCMCIA slot on the back of HDTV sets.

Any how version 1.0 came out last year from I understand and it has a few draw backs. Information only flows one-way with CableCARD. So with CableCARD you are not able to use Pay-per-view because the card only receives signals from the cable company it does not send information out to them. Seems like a lot of people are already waiting for CableCARD 2.0 to come out to address the short comings of version 1.0.

So CableCARD from a hardware view is just another implementation of the PCMCIA card. Why they used the out-dated PC Card interface escapes me.

Here is the new CableCARD listing.

PCIe Card Size

I added this page which shows the dimensions of the PCI Express Board
http://www.interfacebus.com/PCIe_Card_Dimensions.html

New Page Additions

I've been adding some new pages over the last few weeks;

http://www.interfacebus.com/HTX_Daughter_Card_Manufacturers.html

http://www.interfacebus.com/COTS_VPX_Board_Manufacturers.html

http://www.interfacebus.com/COTS_VXS_Board_Manufacturers.html

http://www.interfacebus.com/Test_Equipment_Thermal_Imagers_Manufacturers.html

http://www.interfacebus.com/GPS_Receiver_Manufacturers.html


http://www.interfacebus.com/WebCam_Manufacturers.html

VME Bus

The VME interface still seems to be in high demand. There are a number of pages which deal with the VME bus, and the manufacturers which produce components and equipment on http://www.interfacebus.com/.

The main page that deal with the topic is the VME Bus page. Additional pages include Board manufacturers, Chassis manufacturers, Backplane manufacturers, and a number of pages providing Connector Pinouts.