User`s manual

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Bus Speed Frequency
SDRAM 66 MHz
V3-PCI Bridge 66 MHz
SMSC Ethernet 66 MHz
I/O Expansion 66 MHz
Timers
The SH7709A/7729 and 64465 chips provide five hardware timers to support Windows CE
and other operating system. Under Windows CE two of these timers are assigned for kernel
tasks, while the other three are available for user tasks.
The Timer 1 on the SH7709A/7729 is assigned to periodically interrupt the CPU. This timer is
capable of being programmed to generate periods from 1 millisecond (mS) to 100mS in 2 uS
increments.
The current value (count) of the timer is readable during the interval between interrupts.
This timer has an accuracy of 0.72 µs and has a resolution of 0.72 µs with a system clock of
66MHz, CPU clock set at 133.333MHz, Peripheral clock divide of 6 and a timer clock pre-
scale of 1/16.
Software can change the period of this timer, setting a different interrupt period for each
interrupt event.
The SH7709A/7729 includes a built-in real time clock (RTC with an input clock rate of 16.384
kHz) capable of lasting an elapsed time of greater than one day. It is capable of generating an
interrupt to the processor any time of day within 1 second of its programmed time.
Debug Ethernet Port
Key West supports a 10/100BaseT Ethernet in full or half duplex. An LED indicates the
10/100 rate, Full/Half duplex with Activity and Link status. The design is compliant with IEEE
802.3 100BASE-T specifications and flow control.
Frame Buffer memory supports 64 outstanding transmit and receive packets (128kB of
memory).
Product RS-232 port
The HD64465 on the Tahoe board provides a full RS-232 connected to an external DB9
connector.
The HD64465 UART module is 16550 compatible. This module performs the serial to parallel
conversion on received data, and parallel to serial conversion on transmitted data. Individually,
it contains a programmable baud rate generator that is capable of dividing the input clock by a
number from 1 to 65535; the data rate of each can also be programmed from 115.2K baud
down to 50 baud. The character options are programmable for 1 start bit; 1, 1.5, or 2 stop bits;
even, odd, stick or no parity; and privileged interrupts.
Features
• Programmable FIFO or character mode
• In FIFO mode 16-byte FIFO buffer on the transmitter and receiver
• The programmable Baud rate generator allows the division of input clock by 1 to 2
16
-1
and generates internal 16X clock
• MODEM control function (CTS#, RTS#, DTR#, DSR#, RI#, DCD#)
• Fully programmable serial-interface characteristics:
• 5, 6, 7 or 8 bit characters
• Even, odd, forced 0/1 or no parity bit generation and detection
• 1 ½, or 2 stops bit generation
• Baud rate generation (DC to 115.2K baud)