6.1.3. Function and operation of module

Operations described are:

Memory initialization from local data file

On simulation initialization, the external RAM module loads in data from the file specified in the instantiating top-level memory module. This must be stored as a two-hex character per line data file, which cannot contain more data than the model supports. An example file ram.dat is shown in Example 6.1.

Example 6.1. 


The default configuration for the external RAM modules is in groups of four, which are used to allow memory accesses of full 32-bit words, with a byte stored in each memory module.

Memory read and write from external bus

The external RAM is accessed by transfers through the static memory interface module, allowing both reads from memory and writes to memory. These are performed as 32-bit word transfers, with each byte connected to one of the four memory models.

See Static memory interface for timing diagrams showing read and write transfers to external memory.

Copyright © 2001 ARM Limited. All rights reserved.ARM DDI 0226A