Pci Interface; Low Pin Count Interface (Lpc); Serial Peripheral Interface (Spi); Compatibility Module (Mda Controller, Timer/Counters, Interrupt Controller) - Dell PowerEdge R310 Technical Manual

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PCI Interface

9.7
The Intel 3420 PCI interface provides a 33 MHz, Revision 2.3 implementation. The Intel 3420 integrates a PCI
arbiter that supports up to four external PCI bus masters in addition to the internal Intel 3420 requests. This
allows for combinations of up to four PCI down devices and PCI slots.

Low Pin Count Interface (LPC)

9.8
The Intel 3420 implements an LPC Interface as described in the LPC 1.1 Specification. The Low Pin Count
(LPC) bridge function of the Intel 3420 resides in PCI Device 31:Function 0. In addition to the LPC bridge
interface function, D31:F0 contains other functional units including DMA, interrupt controllers, timers,
power management, system management, GPIO, and RTC.

Serial Peripheral Interface (SPI)

9.9
The Intel 3420 implements an SPI Interface as an alternative interface for the BIOS flash device. An SPI flash
device can be used as a replacement for the FWH, and is required to support Gigabit Ethernet, Intel
Management Technology and integrated Intel Quiet System Technology. The Intel 3420 supports up to two
SPI flash devices with speed up to 50 MHz utilizing two chip select pins.
Compatibility Module (MDA Controller, Timer/Counters, Interrupt
9.10
Controller)
The DMA controller incorporates the logic of two 82C37 DMA controllers, with seven independently
programmable channels. Channels 0–3 are hardwired to 8-bit, count-by-byte transfers, and channels 5–7 are
hardwired to 16-bit, count-by-word transfers. Any two of the seven DMA channels can be programmed to
support fast Type-F transfers.
Channel 4 is reserved as a generic bus master request.
The Intel 3420 supports LPC DMA, which is similar to ISA DMA, through the Intel 3420's DMA controller. LPC
DMA is handled through the use of the LDRQ# lines from peripherals and special encoding on LAD[3:0] from
the host. Single, Demand, Verify, and Increment modes are supported on the LPC interface.
The timer/counter block contains three counters that are equivalent in function to those found in one 82C54
programmable interval timer. These three counters are combined to provide the system timer function, and
speaker tone. The 14.31818 MHz oscillator input provides the clock source for these three counters.
The Intel 3420 provides an ISA-Compatible Programmable Interrupt Controller (PIC) that incorporates the
functionality of two, 82C59 interrupt controllers. The two interrupt controllers are cascaded so that 14
external and two internal interrupts are possible. In addition, the Intel 3420 supports a serial interrupt
scheme.
All of the registers in these modules can be read and restored. This is required to save and restore system
state after power has been removed and restored to the platform.

Advanced Programmable Interrupt Controller (APIC)

9.11
In addition to the standard ISA compatible Programmable Interrupt controller (PIC) described in the previous
section, the Intel 3420 incorporates the Advanced Programmable Interrupt Controller (APIC).

Universal Serial Bus (USB) Controllers

9.12
The Intel 3420 contains up to two Enhanced Host Controller Interface (EHCI) host controllers that support
USB high-speed signaling. High-speed USB 2.0 allows data transfers up to 480 Mb/s. The PCH also contains
two Rate Matching Hubs (RMH) that support USB full speed and low-speed signaling.
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