Local Bus To Industrypack Addressing; 8-Bit Memory Space - Motorola MVME162FX Programmer's Reference Manual

Local Bus to IndustryPack Addressing

The following sections provide examples that illustrate local bus
versus IndustryPack addressing for different IndustryPack spaces
and programmed port widths. Throughout the examples LBA
refers to the local bus address defined by LA<23-0>, and IPA refers
to the IndustryPack address. IPA<22-7> is the value on signal pins
IPAD<15-0>/IPBD<15-0> during the select state (these only apply
to memory accesses); IPA<6-1> is the value on signal pins IPA<6-
1>; and IPA<0> is the value inferred by IPBS1*, where IPA<0> is 0
if IPBS1* is asserted and 1 if IPBS1* is negated.

8-Bit Memory Space

This example is for IP_a, where the IP_a memory space is
programmed with a base address of $00000000, a size of 4MB, and
a port width of 8 bits. The relationship of the IndustryPack address
to the local bus address is: IPA=(LBA*2)+1.
LBA
$00000000
$00000001
$00000002
$00000003
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$003FFFFC
$003FFFFD
$003FFFFE
$003FFFFF
Local Bus to IndustryPack Addressing
IPA
$000001
$000003
$000005
$000007
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$7FFFF9
$7FFFFB
$7FFFFD
$7FFFFF
Comments
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