MC9S08DZ60MLF Datasheet, PDF (53/416 Pages) Freescale Semiconductor, Inc – MC9S08DZ60 Series Features

• Burst programming capability
• Sector erase abort
Chapter 4 Memory
4.5.2 Program and Erase Times
Before any program or erase command can be accepted, the Flash and EEPROM clock divider register
(FCDIV) must be written to set the internal clock for the Flash and EEPROM module to a frequency
(f_FCLK) between 150 kHz and 200 kHz (see Section 4.5.11.1, “Flash and EEPROM Clock Divider
Register (FCDIV)”). This register can be written only once, so normally this write is performed during
reset initialization. The user must ensure that FACCERR is not set before writing to the FCDIV register.
One period of the resulting clock (1/f_FCLK) is used by the command processor to time program and erase
pulses. An integer number of these timing pulses is used by the command processor to complete a program
or erase command.
Table 4-6 shows program and erase times. The bus clock frequency and FCDIV determine the frequency
of FCLK (f_FCLK). The time for one cycle of FCLK is t_FCLK = 1/f_FCLK. The times are shown as a number
of cycles of FCLK and as an absolute time for the case where t_FCLK = 5 μs. Program and erase times
shown include overhead for the command state machine and enabling and disabling of program and erase
voltages.
Table 4-6. Program and Erase Times
Parameter
Byte program
Burst program
Sector erase
Mass erase
Sector erase abort
1 _{Excluding start/end overhead}
Cycles of FCLK
9
4
4000
20,000
4
Time if FCLK = 200 kHz
45 μs
20 μs¹
20 ms
100 ms
20 μs¹
4.5.3 Program and Erase Command Execution
The FCDIV register must be initialized after any reset and any error flag is cleared before beginning
command execution. The command execution steps are:
1. Write a data value to an address in the Flash or EEPROM array. The address and data information
from this write is latched into the Flash and EEPROM interface. This write is a required first step
in any command sequence. For erase and blank check commands, the value of the data is not
important. For sector erase commands, the address can be any address in the sector of Flash or
EEPROM to be erased. For mass erase and blank check commands, the address can be any address
in the Flash or EEPROM memory. Flash and EEPROM erase independently of each other.
MC9S08DZ60 Series Data Sheet, Rev. 4
Freescale Semiconductor
53