Open Compute Project • DC-SCM Specification
http://opencompute.org 1
Table of Contents
1 Overview ....................................................................................................................................................... 5
1.1 DC-SCM Architecture .................................................................................................................................... 6
2 Mechanical .................................................................................................................................................... 7
2.1 Form Factor Options ..................................................................................................................................... 7
2.2 Horizontal Form Factor ................................................................................................................................ 8
2.2.1 Horizontal Form Factor Dimensions ....................................................................................................... 8
2.2.2 Horizontal Form Factor Keep Out Zones.................................................................................................. 9
2.2.3 Horizontal Form Factor I/O Faceplate ................................................................................................... 10
2.3 Vertical Form Factor ................................................................................................................................... 11
2.3.1 Vertical Form Factor Dimension Outline ............................................................................................... 11
3 Interface Definition ..................................................................................................................................... 16
3.1 DC-SCI Card Edge Connector Definition ...................................................................................................... 16
3.1 Gold Finger Plating Requirements .............................................................................................................. 17
3.2 HPM Connector Definition .......................................................................................................................... 17
3.2.1 Straddle Mount Connector .................................................................................................................... 17
3.2.2 Right Angle Connector ........................................................................................................................... 19
3.2.3 Vertical Connector ................................................................................................................................. 20
3.3 DC-SCI Pin Definition .................................................................................................................................. 20
3.4 DC-SCI Signal Descriptions .......................................................................................................................... 23
3.4.1 NC-SI ...................................................................................................................................................... 23
3.4.2 eSPI/SSIF ................................................................................................................................................ 23
3.4.3 Serial GPIO ............................................................................................................................................. 24
3.4.4 I2C .......................................................................................................................................................... 26
3.4.5 I3C .......................................................................................................................................................... 27
3.4.6 SPI .......................................................................................................................................................... 28
3.4.7 USB ......................................................................................................................................................... 30
3.4.8 PCIe ........................................................................................................................................................ 31
3.4.9 PECI ........................................................................................................................................................ 32
3.4.10 UARTS ................................................................................................................................................ 32
3.4.11 JTAG ................................................................................................................................................... 33
3.4.12 Standby Power and Boot Sequence .................................................................................................. 34
3.4.13 Battery Voltage .................................................................................................................................. 37
3.4.14 Miscellaneous Signals ........................................................................................................................ 37
4 Electrical Specifications ............................................................................................................................... 38
4.1 Input Voltage, Power, and Current ............................................................................................................. 38
4.2 SCM Presence Detection and Power Protection ......................................................................................... 38
5 Routing Guidelines and Signal Integrity ....................................................................................................... 39
