Motorola MPC823e - Page 987

PCMCIA Interface
MOTOROLA MPC823e REFERENCE MANUAL 17-21
PCMCIA INTERFACE
17
PRS—PCMCIA Region Select
000 = Common memory space.
001 = Reserved.
010 = Attribute memory space.
011 = I/O space.
100 = DMA (normal DMA transfer.
101 = DMA last transaction.
110 = Drive the value of the A22 and A23 signals on CE2
and CE1.
111 = Reserved.
The “DMA” encoding will generate a normal DMA transfer unless signaled as “last” by the
on-chip DMA controller. In this case, TC (OE
) or TC (WE) is asserted. The “DMA last
transaction” encoding will generate a DMA transfer with TC (OE
) or TC (WE) asserted,
regardless of any internal indication.
PSLOT—PCMCIA Slot Identifier
0 = Reserved.
1 = This window defined for slot B.
WP—Write-Protect
0 = This window is not write-protected.
1 = This window is write-protected. If you try to write to this window, a bus error
(machine check interrupt) will occur.
PV—PCMCIA Valid
This bit indicates that the contents of the PCMCIA base register and option register pair are
valid.
0 = This bank is invalid.
1 = This bank is valid