AMD 4.4.5 Switch User Manual

AMD Confidential
User Manual November 21
, 2008
Chapter 7: Device Configuration 81
7.7 Memory Device
The memory device enables you to add memory devices to the system. You can
configure the memory device for emulation of ROM or dynamic memory. You specify
the total memory size and the beginning address to which the device should respond.
The memory device can also be configured as a LPC flash device. It currently models
2Mb (SST49LF020A), 4Mb (SST49LF040A), 8Mb (SST49LF080A) and 16Mb
(SST49LF160C) flash memory devices. Note that we support two command sequences
used generally by flash memory - SST and ATMEL. User should configure the flash
memory to the appropriate command sequence to get desired results. The SST49LF160C
device uses the ATMEL command sequence while
SST49LF020A/SST49LF040A/SST49LF080A use the SST command sequence.
The memory device has a general-purpose interface that you can connect to any other
type of port. No selection is necessary when connecting this memory device to another
Initialization and Reset State
The default state of the device is a RAM memory device that is at a base address of
0x00000000 and a size of 4 Gigabytes. The memory has no default content. When an
initialization file is specified, the memory device's contents contain the data from that
binary file.
After a reset, the memory device reverts back to the initialization file contents.
Contents of a BSD
The contents of memory, as well as all configuration information, are stored in the BSD.
Configuration Options
The first field of the Memory Configuration tab, shown in Figure 7-14, is the base
address of the device in a hexadecimal value.
The second field is the total size of the memory device, given in decimal value for the
number of 32-Kbyte blocks you would like created (32-Kbyte blocks are used because
non-initialized memory is dynamically allocated when addressed in 32-Kbyte chunks).
The third field is the name of the binary file you use to initialize the memory contents.
The device initializes memory for the content length of the file. If you specify a 512-
Kbyte ROM and use a 256-Kbyte image file, the first 256 Kbytes are initialized. The Init
File selection comes with a browse button for easier selection.
Selecting the Read-Only option turns the memory device into a ROM. Writes to the
device are ignored when the Read-Only option is selected.