User`s manual

Rabbit 4000 Designer’s Handbook rabbit.com 79
10. Supported Flash Memories
There are several flash memories that have been qualified for use with the Rabbit 4000 microprocessor.
Both small and large sector flash devices are supported. To incorporate a large-sectored flash into an end
product, the best strategy is have a small-sectored development board.
10.1 Supporting Other Flash Devices
Rabbit does not support flash devices other than those listed in Table 10-1. However, if you wish to use
another flash memory, one that still uses the same standard 8-bit JEDEC write sequences as one of the sup-
ported flash devices, the existing Dynamic C flash libraries may be able to support it simply by modifying
a few values. Not all flash devices can be supported, and the degree of support will vary depending on the
flash characteristics.
There are two modifications to be made, depending on the version of Dynamic C that you are using. Step
through the list below and perform each action that corresponds to your flash type:
1. The flash device needs to be added to the list of known flash types. This table can be found by search-
ing for the label FlashData in the file LIB\Rabbit4000\BIOSLIB\FLASHWR.LIB. The for-
mat is described in the file and consists of the flash ID code, the sector size in bytes, the total number of
sectors, and the flash write mode.
See the comments above the “FlashData::” table in FLASHWR.LIB for more information.
2. The same information that was added to the FlashData table needs to be added to the FLASH.INI
file (in the main directory where Dynamic C was installed) for use by the compiler and pilot BIOS. See
the top of the file for more information.
Table 10-1 Flash Devices for Rabbit 4000-Based Designs
Device Name
Device Size
(bytes)
Write Mode Operating Voltage Dynamic C Support
SST39LF040 512x8 byte 3.0-3.6V Starts w/ version 10
SST39VF040-70-41 512x8 byte 2.7-3.6V Starts w/ version 10
SST39LF040-45-4C 512Kx8 byte 3.0-3.6V Starts w/ version 10
SST39LF400A-55-4C 256Kx16 word 3.0-3.6V Starts w/ version 10
SST39LF800A-55-4C 512Kx16 word 3.0-3.6V Starts w/ version 10