user manual

Memory Maps
3-7
3
Notes:
1. For a complete description of the register bits, refer to the data
sheet for the specific chip. For a more detailed memory map, refer
to the following detailed peripheral device memory maps.
2. On the MVME177 this area does not return an acknowledge
signal. If the local bus timer is enabled, the access times out and
terminates by a TEA signal.
3. Byte reads should be used to read the interrupt vector. These
locations do not respond when an interrupt is not pending. If the
local bus timer is enabled, the access times out and terminates by a
TEA signal.
4. Writes to the LCSR in the VMEchip2 must be 32 bits. LCSR writes
of 8 or 16 bits terminate with a TEA signal. Writes to the GCSR may
be 8, 16 or 32 bits. Reads to the LCSR and GCSR may be 8, 16 or 32
bits.
5. This area does not return an acknowledge signal. If the local bus
timer is enabled, the access times out and terminates by a TEA
signal.
6. This area does return an acknowledge signal.
7. Size is approximate.
$FFF77000 - $FFF77FFF Reserved -- 4KB 2
$FFF78000 - $FFF7EFFF Reserved -- 28KB 6
$FFF7F000 - $FFF7FFFF Reserved -- 4KB 2
$FFF80000 - $FFF9FFFF Reserved -- 128KB 6
$FFFA0000 - $FFFBFFFF Reserved -- 128KB 5
$FFFC0000 - $FFFCFFFF DS1643/MK48T08 (BBRAM,
TOD Clock)
D32-D8 64KB 1
$FFFD0000 - $FFFDFFFF Reserved -- 64KB 5
$FFFE0000 - $FFFEFFFF Reserved -- 64KB 2
Table 3-2. Local I/O Devices Memory Map (Continued)
Address Range Devices Accessed Port Size Size Notes