requirement is because the eight megabyte space reserved for ex-
pansion in the current machine begins at hex 200000 (See auto-con-
fig notes below).
Auto-Config Notes
1) There is currently no provision for 6MB PICs. Designers of
8
MB
memory boards should consider auto-configs as two
PlCs to al-
low partial loading flexibility.
2) PIC
sizelalignment rules are subject to change. If so, bit(s) will be
defined to allow a PIC to specify that
it
is more flexible than the
old rules require.
3)
The address map is subject to change.
A
PIC should assume that
it
may be placed anywhere in the address space.
4)
All expansion devices are strongly encouraged to use the auto-
config protocols. Assignment of fixed I10 addresses
is
subject to
negotiation.
Address Specification Table
All
nibbles except 00, 02,40 and
42
should be inverted.
Descriptions:
3
2
1
0
Board type and size
I
l
L~'
Memory size
000
=
8
megabytes
001
=
64
kilobytes
0
1
0
=
128 kilobytes
01 l
=
256 kilobytes
100
=
51 2 kilobytes
101
=
1 megabyte
1
10
=
2
megabytes
1 1 1
=
4
megabytes
L
Chained config request, indicates that the next
auto-config device in the daisy chain
is
physically
tied to this device.
Optional ROM vector valid
I
L
Link into memory free
list
L
Board type
00
=
Reserved
01
=
Reserved
10
=
Reserved
1 1
=
Current style board
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