Motorola MVME172 manual IP to Local Bus Data Routing, Memory Space Accesses

Models: MVME172

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IP2 Chip

IP to Local Bus Data Routing

This section shows data routing from an IP to the local bus.

Memory Space Accesses

The following table shows the data routing when accessing IP memory space.

IPWIDTH refers to the memory space width that has been programmed into the general control register for the IndustryPack being accessed.

LBSIZE refers to local bus transfer size.

LBA refers to local bus address signals 1 and 0.

LD refers to the local data bus.

IPA refers to IndustryPack address signals 2,1,0. The IP2 chip implements dynamic bus sizing for memory space accesses whose local bus size is greater than the port width of the IndustryPack that is being accessed. Because of this, the IP2 chip performs 1, 2 or 4 IP memory space cycles for each local bus cycle. The IPA column in the table lists 1, 2, or 4 addresses to indicate the address for each IP cycle that is performed.

IPXD refers to the IP_a data bus (IPAD) when accessing IP_a or IP_c. It refers to the IP_b data bus (IPBD) when accessing IP_b or IP_d.

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Motorola MVME172 manual IP to Local Bus Data Routing, Memory Space Accesses