tmp19a43fd TOSHIBA Semiconductor CORPORATION, tmp19a43fd Datasheet - Page 46

• Manufacturer Part Number: tmp19a43fd
• Description: 32-bit Risc Microprocessor
• Manufacturer: TOSHIBA Semiconductor CORPORATION

3.3.11
Password
Following an echo-back of the command code, the boot program checks the contents of the 12-byte
password area (0x4000_0474 to 0x4000_047F) within the flash memory. If all these address locations
contain the same bytes of data other than FFH, a password area error occurs. In this case, the boot
program returns an error acknowledge (11H) in response to the checksum byte (the 17th byte),
regardless of whether the password sequence sent from the controller is all FFHs.
stored in the flash memory. Table 3.9 shows how they are compared byte-by-byte. All of the 12 bytes
must match to pass the password check. Otherwise, a password error occurs, which causes the boot
program to return an error acknowledge in response to the checksum byte (the 17th byte).
The RAM Transfer command (10H) causes the boot program to perform a password check.
The password sequence received from the controller (5th to 16th bytes) is compared to the password
Figure 3.4 Serial Operation Mode Determination Flow
Are all bytes the same?
tCD m tAD  tAC
Password area error
Are all bytes equal to
UART Mode
tAB ! tCD?
Figure 3.5 Password Area Check Flow
Start
Start
FFH?
No
Yes
TMP19A43 (rev2.0)3-32
Yes
No
Yes
Password area is normal.
I/O Interface Mode
Flash Memory Operation
TMP19A43