Electrical Characteristics
S12XS Family Reference Manual, Rev. 1.13
Freescale Semiconductor
679
A.3
NVM, Flash
A.3.1
Timing Parameters
The time base for all NVM program or erase operations is derived from the oscillator. A minimum
oscillator frequency f
NVMOSC
is required for performing program or erase operations. The NVM modules
do not have any means to monitor the frequency and will not prevent program or erase operation at
frequencies above or below the specified minimum. When attempting to program or erase the NVM
modules at a lower frequency, a full program or erase transition is not assured.
The program and erase operations are timed using a clock derived from the oscillator using the FCLKDIV
register. The frequency of this clock must be set within the limits specified as f
NVMOP
.
The minimum program and erase times shown in
are calculated for maximum f
NVMOP
and
maximum f
NVMBUS
unless otherwise shown. The maximum times are calculated for minimum f
NVMOP
A.3.1.1
Erase Verify All Blocks (Blank Check) (FCMD=0x01)
The time it takes to perform a blank check is dependant on the location of the first non-blank word starting
at relative address zero. It takes one bus cycle per phrase to verify plus a setup of the command. Assuming
that no non blank location is found, then the erase verify all blocks is given by.
A.3.1.2
Erase Verify Block (Blank Check) (FCMD=0x02)
The time it takes to perform a blank check is dependant on the location of the first non-blank word starting
at relative address zero. It takes one bus cycle per phrase to verify plus a setup of the command. Assuming
that no non blank location is found, then the erase verify time for a single 256K NVM array is given by
For a 128K NVM or D-Flash array the erase verify time is given by
A.3.1.3
Erase Verify P-Flash Section (FCMD=0x03)
The maximum time depends on the number of phrases being verified (N
VP
)
t
check
33500
1
f
NVMBUS
---------------------
⋅
=
t
check
33500
1
f
NVMBUS
---------------------
⋅
=
t
check
17200
1
f
NVMBUS
---------------------
⋅
=
t
check
752
N
VP
+
(
)
1
f
NVMBUS
---------------------
⋅
=
Содержание MC9S12XS128
Страница 4: ...S12XS Family Reference Manual Rev 1 13 4 Freescale Semiconductor ...
Страница 58: ...Device Overview S12XS Family S12XS Family Reference Manual Rev 1 13 58 Freescale Semiconductor ...
Страница 150: ...Memory Mapping Control S12XMMCV4 S12XS Family Reference Manual Rev 1 13 150 Freescale Semiconductor ...
Страница 168: ...Interrupt S12XINTV2 S12XS Family Reference Manual Rev 1 13 168 Freescale Semiconductor ...
Страница 194: ...Background Debug Module S12XBDMV2 S12XS Family Reference Manual Rev 1 13 194 Freescale Semiconductor ...
Страница 364: ...Periodic Interrupt Timer S12PIT24B4CV1 S12XS Family Reference Manual Rev 1 13 364 Freescale Semiconductor ...
Страница 396: ...Pulse Width Modulator S12PWM8B8CV1 S12XS Family Reference Manual Rev 1 13 396 Freescale Semiconductor ...
Страница 506: ...Voltage Regulator S12VREGL3V3V1 S12XS Family Reference Manual Rev 1 13 506 Freescale Semiconductor ...
Страница 736: ...Ordering Information S12XS Family Reference Manual Rev 1 13 736 Freescale Semiconductor ...
Страница 737: ......