2192-12132-000-000
Bits
PC104 IRQ
Bit 0
IRQ3
Bit 1
IRQ4
Bit 2
IRQ5
Bit 3
IRQ6
Bit 4
IRQ7
Bit 5
IRQ10
Bit 6
IRQ14
Bit 7
IRQ15
Writing a ‘1’ to a relevant bit will clear the interrupt.
CompactFlash
Slot 0 of the on chip PC Card controller is connected to the CompactFlash connector to create a
hot swappable 3.3V interface.
Start Address
Region Name
0x2C00 0000
Socket 0 Common Memory Space
0x2800 0000
Socket 0 Attribute Memory Space
0x2400 0000
Reserved
0x2000 0000
Socket 0 I/O Space
GP9 on the PXA255 is used to detect a card being inserted. Detecting a falling edge will
indicate a CompactFlash card has been inserted.
GP8 is used as the interrupt for the CompactFlash (RDY/nBSY).
GP82 controls the power switch for the CompactFlash interface, setting this to logic high will
enable the 3.3V supply to the connector.
Real Time Clock
The accuracy of the Real Time Clock is based on the operation of the 32.768KHz watch crystal.
This will provide an accuracy of +/-1 minute per month if the board is in an ambient environment
of +25
O
C. When the board is operated outside this temperature then the accuracy may be
degraded.
There are two RTC’s on the VIPER, one is contained within the PXA255 device, this is not
battery backed, but is only used for power management events. A Dallas DS1307 RTC is used
to keep time and date and can be battery backed using an external battery.
The following PXA255 GP lines are used to control the DS1307
PXA255 GP
Function
GP84 Clk
GP83 Data
A data sheet for the Dallas RTC device is available on a Development Kit CD.
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