What is the usage of the EEPROM in embedded application? can you give me examples?
As noted in the comments my answer to EEPROM is a Read Only Memory so why can I write to it? provides some relevant information.
Table 1. Summary of memory type features.
WRITEABLE ERASABLE RETENTIVE Notes ===================================================================== RAM Yes Yes No Data loss on power cycle. ROM At factory No Yes Data designed in. PROM Yes No Yes Data user programmable. EPROM Yes With UV Yes Wipe contents with UV light. EEPROM Yes Yes Yes Change data while running.
The main benefit of EEPROM is that it is writeable like RAM (but much more slowly) but unlike RAM the data will survive a power cycle. It's typically used to store configuration settings or data that should survive a power cycle. Examples include devices such as a printer where parameters such as IP address, paper size, etc. and data such as total page count need to be restored on power-up.