mc9s12ne64 Freescale Semiconductor, Inc, mc9s12ne64 Datasheet - Page 89

• Manufacturer Part Number: mc9s12ne64
• Description: Hcs12 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

2.4.1.2
The Flash command controller is used to supervise the command write sequence to execute program,
erase, erase verify, and data compress algorithms.
Before starting a command write sequence, the ACCERR and PVIOL flags in the FSTAT register must be
clear (see
determine the state of the address, data, and command buffers. If the CBEIF flag is set, indicating the
buffers are empty, a new command write sequence can be started. If the CBEIF flag is clear, indicating the
buffers are not available, a new command write sequence will overwrite the contents of the address, data,
and command buffers.
A command write sequence consists of three steps which must be strictly adhered to with writes to the
Flash module not permitted between the steps. However, Flash register and array reads are allowed during
a command write sequence. A command write sequence consists of the following steps:
A command write sequence can be aborted prior to clearing the CBEIF flag by writing a 0 to the CBEIF
flag and will result in the ACCERR flag being set.
Freescale Semiconductor
1. Write an aligned data word to a valid Flash array address. The address and data will be stored in
2. Write a valid command to the FCMD register.
3. Clear the CBEIF flag by writing a 1 to CBEIF to launch the command. When the CBEIF flag is
the address and data buffers, respectively. If the CBEIF flag is clear when the Flash array write
occurs, the contents of the address and data buffers will be overwritten and the CBEIF flag will be
set.
a) For the erase verify command (see
b) For the data compress command (see
c) For the program command (see
d) For the sector erase command (see
e) For the mass erase command (see
f) For the sector erase abort command (see
cleared, the CCIF flag is cleared on the same bus cycle by internal hardware indicating that the
command was successfully launched. For all command write sequences except data compress and
sector erase abort, the CBEIF flag will set four bus cycles after the CCIF flag is cleared indicating
that the address, data, and command buffers are ready for a new command write sequence to begin.
For data compress and sector erase abort operations, the CBEIF flag will remain clear until the
operation completes.
Section 2.3.2.7, “Flash Status Register
of the data buffer are ignored and all address bits in the address buffer are ignored.
contents of the data buffer represents the number of consecutive words to read for data
compression and the contents of the address buffer represents the starting address.
data buffer will be programmed to the address specified in the address buffer with all address
bits valid.
of the data buffer are ignored and address bits [9:0] contained in the address buffer are ignored.
the data buffer and address buffer are ignored.
the contents of the data buffer and address buffer are ignored.
Command Write Sequence
MC9S12NE64 Data Sheet, Rev. 1.1
Section 2.4.1.3.3, “Program
Section 2.4.1.3.5, “Mass Erase
Section 2.4.1.3.4, “Sector Erase
Section 2.4.1.3.1, “Erase Verify
Section 2.4.1.3.2, “Data Compress
(FSTAT)”) and the CBEIF flag must be tested to
Section 2.4.1.3.6, “Sector Erase Abort
Command”), the contents of the
Command”), the contents of
Command”), the contents
Command”), the contents
Command”), the
Functional Description
Command”),
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