Flash Versus Eeprom; Dual Operation - Renesas FSL-T06 User Manual

Flash Self-Programming Library

1.1 Flash versus EEPROM

1.2 Dual Operation

Note
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User Manual
Major difference between Flash and EEPROM (or E
reprogramming granularity. EEPROM can be reprogrammed wordwise, where
the size of one word depends on the organization and interface. It can vary in the
wide range between 8 bit and 256 bytes.
Depending on the implementation, Flash may also be programmed wordwise, but
the Erase can only be done on a complete block. This is the major limitation of
Flash against EEPROM, but due to that the memory hardware effort can be
reduced significantly, making the embedded non volatile memory for program
code affordable.
Common for all Flash implementations is, that during Flash modification
operations (Erase/Write) a certain amount of Flash memory is not accessible for
any read operation (e.g. program execution or data read).
This does not only concern the modified Flash range, but a certain part of the
complete Flash system. The amount of not accessible Flash depends on the
device architecture.
A standard architectural approach is the separation of the Flash into Code Flash
and Data Flash. By that, it is possible to read from the Code Flash (to execute
program code or read data) while Data Flash is modified, and vice versa.
To check whether Dual Operation is supported by a device, please refer to the
device user manual.
It is not possible to modify Code Flash and Data Flash in parallel
2
PROM) is the
Introduction
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