Open Specifications for
Myrinet-2000 Switch Line Cards

The files linked from this page provide the information required to design line cards compatible with Myricom's Myrinet-2000 switch line cards and enclosures, or to use any of these line cards with other types of packaging. A company or research group might, for example, build an 8-node multicomputer on a line card that could be used in a Myricom enclosure, or might use a line card for SAN-Serial or SAN-Fiber conversion from a special-purpose system.

Here is a photograph of a typical Myrinet-2000 switch line card (Myricom product code M3-SW16-8S):

and here is a block diagram with roughly the same spatial relationships between the parts:

The numbers 0 ... 7 on the backplane interface and 8 ... 15 on the front-panel ports correspond to the XBar16 port numbers.

In terms of VME and IEEE 1101.10 specifications, these line cards would be described as "9U-220mm." The only unconventional characteristics are that the line cards are horizontal in Myricom enclosures, and that the EMI gasketing on the front panel is down relative to the illustrations above (on the left if the line cards were vertical). We encourage anyone seeking to design a compatible line card or to package a Myricom line card in other than a Myricom enclosure to examine a Myricom line card card, and to study the Guide to Myrinet-2000 Switches and Switch Networks.

You should start by downloading the following files. It should be possible to print the Postscript (.ps) files on 8.5" x 11" paper on any Postscript printer.

• layout.ps shows the outline and key coordinates of these 9U-220mm line cards.
• e_sig.ps shows the signals on the E connector, e_num.ps is the pin numbering, and e.txt is an ASCII signal list that you may be able to import into your PCB-layout program.
• f_sig.ps shows the signals on the F connector, f_num.ps is the pin numbering, and f.txt is an ASCII signal list that you may be able to import into your PCB-layout program.
• k_sig.ps shows the signals on the K (power) connector, k_num.ps is the pin numbering, and k.txt is an ASCII signal list that you may be able to import into your PCB-layout program.

The signal names given for the E and F connectors are the same as those of the XBar16 2.x, whose pinout is given in documentation linked from http://www.myri.com/vlsi/. Outputs are outputs of the XBar16 and of the line card. Inputs are inputs of the XBar16 and of the line card. For the special pins:

• R = serial input to linecard
• T = serial output from linecard
• K = keying - connected to GND on the backplane, and used to detect when the board is inserted.

The serial-link protocol is 250kbit/sec, 3.3V, RS-232, with 9-bit characters, no parity, and one stop bit. The linecard does not initiate serial transactions, it only responds to transactions started by whatever is on the other end of the serial link (an M3-M monitoring line card in Myricom enclosures). The 9th bit, when set, indicates a special character. Such characters are used to mark the beginning and end of a packet, as well as to indicate certain error conditions. Documentation for the protocols used by the M3-M monitoring line card is forthcoming.

The E and F connectors are AMP "HS-3" connectors. The AMP part numbers for the right-angle board-mount connector are:

• The E connector is composed of an AMP 120675-1 30-signal-pin connector plus a 120673-1 60-signal-pin segment.
• The F connector is composed of an AMP 120676-1 30-signal-pin connector plus a 120673-1 60-signal-pin segment.

The E and F connectors each use one 535875-2 guide pin receptacle with a #2-56 nut and washer.

The K connector is an AMP 223961-1 connector.

The mating connectors can be found in AMP catalogs.

First posted: 30 March 2001
Revised: 6 May 2001 - added board-dimension tolerances to layout.ps file