TC1784
Program Memory Unit (PMU)
User´s Manual
5-20
V1.1, 2011-05
PMU, V1.47
If the Flash bank, which is addressed, is still busy, the command cycle stall the bus
system and the sending master. After the last cycle of the command sequence, the
device automatically starts and controls the erase procedure. Start of operation is
delayed, if another bank is busy with a write operation at that time. Termination of
operation is indicated in the Flash status register and can also be enabled to generate
an end-of-busy interrupt. After erase operation, the Flash memory delivers ‘0’ data with
correct ECC code on read access.
For the physical sectors in Program Flash (64K, 128K and 256K) a maximum number
(endurance) of 1000 erase and program operations is supported. For the (logical)
16K sectors in PFlash max. 100 erase cycles are allowed to the same sector without
refresh (see
). For the Data Flash sectors a maximum number of 60000
erase cycles are defined (can depend on the device).
Besides sector erase, also a special six-cycle block erase operation is available
dedicated only to the User Configuration Blocks (UCB). This operation supports the
change of user-specific Flash configuration regarding protection functions, i.e. the lock
bits or keywords. Since a UC block comprises four pages, a 1 Kbyte block is erased with
this operation. The maximum number of UCB changes is limited to 4. The UCB erase
time is shorter than the sector erase time (max. 500 ms).
As the program operation, also the sector erase operation includes an erase quality
check that identifies incorrectly erased bits in the Flash sector, and that indicates a
verification error if weak bits can no more be corrected (see
An erase operation is executed within max. 5 s (Data Flash: 2.5 s) (but depending on
sector size and on CPU frequency). In Data Flash an automatic erase suspend function
is implemented for immediate execution of program operations to the other DFlash bank.
During an erase operation, the minimum system clock is limited to 1 MHz. A system
reset condition stops an erase operation within max. 250 µsec. Such an error state can
be recognized by proper handling and checking of the ERASE status flag in Flash Status
Register FSR (except for power-on reset).
In-System Programming
In-system programming is fully supported. No special program voltage VPP is required.
Because of the automatic execution of erase and program algorithms, write operations
are reduced to transferring commands and data to the Flash and reading the status (see
for hints). Because of the page assembly function, write data may be
written to the Flash very comfortably and fast. User code that writes data to the
page assembly buffer can be executed also from the same internal Program Flash (in
non-cached operating mode). User code that writes command sequences to the
Program Flash must be executed from memory outside the addressed on-chip Flash
memory (on-chip RAM or if available other Flash module or external memory).
Note: Simultaneous read accesses to Program Flash while erasing or programming the
Data Flash are supported. Thus, command sequences for the Data Flash can be
Содержание TC1784
Страница 1: ...User s Manual V1 1 2011 05 Microcontrollers TC1784 32 Bit Single Chip Microcontroller ...
Страница 3: ...User s Manual V1 1 2011 05 Microcontrollers TC1784 32 Bit Single Chip Microcontroller ...
Страница 950: ...TC1784 Direct Memory Access Controller DMA User s Manual 11 132 V1 1 2011 05 DMA V3 03 ...
Страница 1949: ...TC1784 General Purpose Timer Array GPTA v5 User s Manual 21 297 V1 1 2011 05 GPTA v5 V1 14 ...
Страница 2350: ...w w w i n f i n e o n c o m Published by Infineon Technologies AG Doc_Number ...