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19. Flash Memory
19.2 Command Sequence
TMP86FS64FG
A maximum of 30 ms is required to erase 4 kbytes. The next command sequence cannot be executed until the
erase operation is completed. To check the completion of the erase operation, perform read operations repeat-
edly for data polling until the same data is read twice from the same address in the flash memory. During the
erase operation, any consecutive attempts to read from the same address is reversed bit 6 of the data (toggling
between 0 and 1).
19.2.3 Chip Erase (All Erase)
This command erases the entire flash memory in approximately 30 ms. The next command sequence cannot
be executed until the erase operation is completed. To check the completion of the erase operation, perform
read operations repeatedly for data polling until the same data is read twice from the same address in the flash
memory. During the erase operation, any consecutive attempts to read from the same address is reversed bit 6
of the data (toggling between 0 and 1). After the chip is erased, all bytes contain FFH.
19.2.4 Product ID Entry
This command activates the Product ID mode. In the Product ID mode, the vendor ID, the flash ID, and the
read protection status can be read from the flash memory.
Note: The value at address F002H (flash size) depends on the size of flash memory incorporated in each product. For example, if
the product has 60-kbyte flash memory, "0EH" is read from address F002H.
19.2.5 Product ID Exit
This command is used to exit the Product ID mode.
19.2.6 Read Protect
This command enables the read protection setting in the flash memory. When the read protection is enabled,
the flash memory cannot be read in the parallel PROM mode. In the serial PROM mode, the flash write and
RAM loader commands cannot be executed.
To enable the read protection setting in the serial PROM mode, set FLSCR<BANKSEL> to "1" before exe-
cuting the read protect command sequence. To disable the read protection setting, it is necessary to execute the
chip erase command sequence. Whether or not the read protection is enabled can be checked by reading
FF7FH in the Product ID mode. For details, see Table 19-4.
Table 19-4 Values To Be Read in the Product ID Mode
Address
Meaning
Read Value
F000H
Vendor ID
98H
F001H
Flash macro ID
41H
F002H
Flash size
0EH:
60 kbytes
0BH:
48 kbytes
07H:
32 kbytes
05H:
24 kbytes
03H:
16 kbytes
01H:
8 kbytes
00H:
4 kbytes
FF7FH
Read protection status
FFH:
Read protection disabled
Other than FFH: Read protection enabled