I2C Inter-Integrated Circuit

Dell™ PowerEdge™ R610 Technical Guidebook

C. I2C (Inter-Integrated Circuit)

What is I2C? A simple bi-directional 2-wire bus for efficient inter-integrated circuit control. All 2IC-bus compatible devices incorporate an on-chip interface that allows them to communicate directly with each other via the I2C-bus. This design concept solves the many interfacing problems encountered when designing digital control circuits. These I2C devices perform communication functions between intelligent control devices (e.g., microcontrollers), general-purpose circuits (e.g., LCD drivers, remote I/O ports, memories), and application-oriented circuits.

The PowerEdge R610, BIOS accesses the I2C through the ICH9 (Intel I/O Controller Hub 9). There are two MUXes on ICH9’s I2C bus.

•One MUX (U_ICH_SPD) controls the DIMM SPDs through four split segments

•The other MUX (U_ICH_MAIN) controls the clock buffers, TOE, USB Hub through four split segments.

BIOS controls both the MUXes through the two select lines using GPIO pins.

Clock chip, USB hub, and the front panel EEPROM device addresses are located on the IOH I2C bus.

Section 10. Embedded NICs / LAN on Motherboard (LOM)

A. Overview / Description

Embedded Gigabit Ethernet Controllers with TCP Offload Engine (TOE) support. Two Broadcom

5709C dual-port Gigabit Ethernet controllers and support circuitry are installed on the system board as independent Ethernet interface devices. From a board perspective, the LOM refers to one of these controllers. From a system perspective, the terms LOM and embedded NIC are interchangeable. LOM1 on the board has two ports: embedded NIC1 and embedded NIC2. These ports could also be called LOM1 and LOM2.

•x4 PCI Express Gen2 capable interface

•The R610 operates this controller at Gen1 speed

•Integrated MAC and PHY 3072x18 Byte context memory

•64KB receive buffer

•TOE (TCP Offload Engine)

•iSCSI controller (enabled through an optional hardware key)

•RDMA controller (RNIC) (enabled post-RTS through an optional hardware key)

•NC-SI (Network Controller-Sideband Interface) connection for manageability

•Wake-On-LAN (WOL)

•PXE 2.0 remote boot

•iSCSI boot

•IPv4 and IPv6 support

•Bare metal deployment support

Section 11. I/O Slots

A. Overview / Description

The PowerEdge R610 requires two PCI Express risers:

•Two PCIe risers (left and center) provide two PCI Express expansion slots, as follows:

•Two x8 PCIe Gen2 slots, connected to the IOH

•One x4 PCIe Gen1 slot for storage on the center riser, connected to the ICH9

•Support for full-height / half-length (6.6" max length) PCIe cards

•System supports 25W maximum power for the first PCIe card and 15W for the second

PCIe card