S912XHZ512F1VAG Datasheet, PDF (908/978 Pages) Freescale Semiconductor, Inc – Covers MC9S12XHZ384, MC9S12XHZ256

Appendix A Electrical Characteristics
A.3.1.3 Sector Erase
Erasing a 1024-byte Flash sector or a 4-byte EEPROM sector takes:
tera ≈ 4000 ⋅ _{f---N----V-----1M-----O-----P--}
The setup time can be ignored for this operation.
A.3.1.4 Mass Erase
Erasing a NVM block takes:
tmass ≈ 20000 ⋅ _{f---N----V-----1M-----O-----P--}
The setup time can be ignored for this operation.
A.3.1.5 Blank Check
The time it takes to perform a blank check on the Flash or EEPROM is dependant on the location of the
first non-blank word starting at relative address zero. It takes one bus cycle per word to verify plus a setup
of the command.
tcheck ≈ location ⋅ tcyc + 10 ⋅ tcyc
MC9S12XHZ512 Data Sheet, Rev. 1.06
908
Freescale Semiconductor