Intel IXP2800 and IXP2850 Network Processors
Functional Units
Datasheet
17
2.8
PCI Controller
The PCI Controller provides a 64-bit, 66 MHz-capable PCI Local Bus Specification, Version 2.2*
interface. It is also compatible to 32-bit and/or 33 MHz PCI devices. The PCI controller provides
the following functions:
Target Access (external Bus Master access to SRAM, DRAM, and CSRs)
Master Access (Intel XScale core or Microengine access to PCI Target devices)
Two DMA Channels
Mailbox and Doorbell Registers for Intel XScale core to host communication
PCI Arbiter
The network processor can be configured to act as a PCI central function (for use in a stand-alone
system), where it provides the PCI reset signal, or as an add-in device, where it uses the PCI reset
signal as the chip reset input.
2.9
GPIO
The network processor contains eight General Purpose I/O (GPIO) pins. These can be programmed
as either input or output, and can be used for slow speed I/O, such as LEDs or input switches. They
can also be used as interrupts to the Intel XScale
core, or to clock the programmable timers.
Figure 7. CSIX Flow Control Interfaces: Simplex and Full Duplex Modes
A9391-02
CSIX RX
Serial
Bus
Flow Control
Bus
CSIX TX
Ingress
Intel IXP2800
Network
Processor
Egress
Intel IXP2800
Network
Processor
Switch
Fabric
Interface
FCIFIFO
MSF
CSIX RX
CSIX Flow Control Interface: Simplex Mode
CSIX Flow Control Interface: Full Duplex Mode
Flow Control TX
Ingress
Intel IXP2800
Network
Processor
Egress
Intel IXP2800
Network
Processor
Switch
Fabric
Interface
FCIFIFO
FCEFIFO
CSIX TX
Flow
Control
RX