VIPER
Detailed hardware description
PC/104 interface
The PC/104 interface supports 8/16 bit ISA bus style signals. Add on boards can be
used to enhance the functionality of the main board. Arcom has an extensive range of
PC/104 compliant modules and these can be used to quickly add digital I/O, analog I/O,
serial ports, video capture devices, PC card interfaces etc. The ISA bus is based on the
x86 architecture and is not normally associated with RISC processors. It shall be
necessary to modify standard drivers to support any 3
rd
party PC/104 modules.
Any PC/104 board plugged in will appear in the PC Card memory space socket 1.
Address Region
Name
0x3D000000 – 0x3FFFFFFF
Reserved
0x3C000000 – 0x3CFFFFFF
PC/104 memory space (16MB)
0x30000400 – 0x3BFFFFFF
Reserved
0x30000000 – 0x300003FF
PC/104 I/O space (1kB)
The PC/104 bus signals are compatible with the ISA bus electrical timing definitions.
DMA, bus mastering, and shared interrupts are not supported on the VIPER’s PC/104
interface. For details on PC/104 Interrupts please see
, page
The VIPER pr5V to a PC/104 add-on-board via the PL11 and PL12 connectors.
If a PC/104 add-on-board requires a +12V supply, then +12V must be supplied to the
VIPER power connector PL16 pin 4. If –12V or –5V are required, these must be
supplied directly to the PC/104 add-on board.
All signals between the PXA255 and the PC/104 are buffered. When access to the
PC/104 bus is not in use the PXA255 socket 1 and the PC/104 connector are
automatically isolated by the buffers transceiver output enables being driven to ‘1’.
© 2004 Arcom Issue H
48