User`s manual

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Section 4 Hardware Description
Functional Description
CPU
The Key West may be configured with either a Hitachi SH7709A or SH7729 SH3 processor.
The processor internal speed runs at 133MHz and the bus speed at 66MHz. Internal CPU
available peripherals include:
• 8 KByte cache
• Two A/D
• D/A
• Limited General Purpose I/O
• Two RS-232 ports
• DMA controller
• Smart Card Interface
In addition to the SH7709A/7729 processor the MQ-200 video chip and HD64465 companion
chip is used for tightly coupled and integrated expansion.
The Hitachi SH7729 processor can also be substituted for the SH7709A, since it is pin
compatible and a functional superset. The SH7729 includes an additional on-chip DSP
processor.
CPU is hard-wired for “little endian” processing for Window CE but can be jumpered for “big
endian” to support other operating systems.
RAM
The Key West contains 64 MB of SDRAM.
Flash Memory
The board supports 32 MB of flash memory. HARP requires a hardware provision determined
by the setting of two of the switches that forces the system to power up and execute directly out
of Flash. In this case Boot PROM is ignored.
The Processor can block erase, and block-protect the Flash at a granularity finer than 1
MB/block. The processor is only able to write to flash memory only while executing out of
Boot PROM.
There is a software controlled, global write protect register bit. This bit prevents the hardware
from asserting the write-enable signal thus disabling all writes to flash memory.
Boot PROM
A boot PROM handles board initialization, flash memory loading, diagnostics and testing. The
boot ROM contains a flash loader that is capable of loading Windows CE into the operating
system flash. The boot PROM circuitry supports a 512KB Flash EPROM.
Monitor code will reside in the Boot PROM. This monitor will use the serial debug port at a
rate of 38.4 kbps (8 data bits, 1 stop bit, and no parity).
LED Status Indicator
• 1 green STATUS
The Green LED is mounted on the faceplate. After power-on, the LED will be forced on by
reset. As soon as the CPU comes out of reset the LED is turned off by software, indicating
successful fetch of the first instructions. When Windows CE is running, the kernel will
periodically toggle the LED, indicating normal operation.
Reset Button
Key West has a push button reset located on the faceplate.