Motorola MVME172 manual Local Bus to IndustryPack Addressing, Bit Memory Space, Comments

Models: MVME172

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IP2 Chip

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

IPA

Comments

 

 

 

$00000000

$000001

 

$00000001

$000003

 

$00000002

$000005

 

$00000003

$000007

 

 

 

 

$003FFFFC

$7FFFF9

 

$003FFFFD

$7FFFFB

 

$003FFFFE

$7FFFFD

 

$003FFFFF

$7FFFFF

 

 

 

 

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Motorola MVME172 manual Local Bus to IndustryPack Addressing, Bit Memory Space, Comments