System information

2.2 Excalibur Chip
SRAM The SRAM is used for fast data storage of the FPGA unit.
SDRAM The SDRAM is the main memory of the embedded system.
Excalibur EPXA1 Chip The EPXA1 contains the CPU and an FPGA unit. It is illus-
trated in section 2.2.
32 bit PCI Connector The card can be plugged into any PCI or PCI-X slot. Bus switches
allow to use the card with 5V and 3.3V PCI slots.
Ethernet Chip An 10/100 MBit Ethernet chip provides the network interface of the
CHARM.
USB Mini Connector The USB mini connectors provide an external USB connection from
the CHARM to the host computer. They are used if the host computer does not provide
an internal USB interface.
External Power Connector Besides PCI and WOL, the CHARM can be powered via a
separate power supply.
2.2 Excalibur Chip
The processing unit of the CHARM is the Excalibur chip [1] of the Altera Corporation [36].
The CHARM uses the EPXA1 chip of the Excalibur family. It contains a hard-core processor
and an FPGA unit. The embedded ARM processor operates with a frequency of up to 200
MHz. An AMBA
2
AHB
3
bus combines the processor with the FPGA. Additional you can
interconnect SDRAM and flash memories, an Ethernet chip or other external devices to the
internal bus system. The Excalibur chip is divided into the Embedded Stripe and the PLD
array (FPGA).
2.2.1 Embedded Stripe
The embedded stripe is the part of the Excalibur chip which contains the peripherals,
memory subsystem and the processor core. Figure 2.2 shows the structure and organization
of the design components which conform this submodule.
The main system bus of the Excalibur chip is the AHB bus and it is divided into two
parts: a fast bus system clocked with the frequency of the ARM processor named AHB1
bus and the AHB2 bus which is clocked with the half of the AHB1 frequency. The AHB
system is connected to other bus systems to access the hardware units of the CHARM.
The address mapping of the bus systems can be found in the appendix E. The SDRAM
module of 32 MB installed on the CHARM is directly connected to the Excalibur device.
2
Advanced Microprocessor Bus Architecture.
3
Advanced High-Performance Bus is a high-performance bus developed by ARM Ltd [37].
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