VIPER
Detailed hardware description
General purpose I/O
Eight general-purpose input lines and eight general-purpose output lines are provided
on connector PL9.
To read from IN[0:7], read the least significant byte from offset 0x500000 of CS5
(0x14500000) to sample the 8 inputs from PL9.
VIPER Inputs
PXA255 data
IN0 D0
IN1 D1
IN2 D2
IN3 D3
IN4 D4
IN5 D5
IN6 D6
IN7 D7
PXA255
Transceiver
PL9
D[0:7]
IN[0:7]
3.3V
10k
ohms
The PXA255 is not designed to interface to 8-bit peripherals, so when the 8-bits of data
are read only the least significant byte from the word contains the data.
Data bus
Most Significant Byte
Least Significant Byte
D15 D14 D13 D12 D11 D10 D9
D8
D7
D6
D5
D4 D3 D2
D1
D0
Don’t Care
IN Data
© 2004 Arcom Issue H
39