tmp89fm42 TOSHIBA Semiconductor CORPORATION, tmp89fm42 Datasheet - Page 371

• Manufacturer Part Number: tmp89fm42
• Description: 8 Bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

RA002
22.12.1.3Password setting, cancellation and authentication
22.12.1.4Password values and setting range
Table 22-21 Password Values and Setting Range
(password count storage address)
(password comparison start
without meeting these conditions is used, a password error occurs. In this case, the TMP89FM42 does not
transmit data and goes into an idle state.
(password count)
Password string
A password must be set in accordance with the conditions shown in Table 22-21. If a password created
Password
address)
• Password setting
• Password cancellation
• Password authentication
PNSA
PCSA
N
routine is unnecessary. A password can be set by simply writing a program to flash memory.
word is canceled when flash memory is all initialized to 0xFF.
0xFFFF of the TMP89FM42, a product is considered a non-blank product, and password
authentication is required to execute an operation command. In this password authentication
process, PNSA, PCSA and a password string are used. An operation command is executed only
if a password has been successfully authenticated. If a password is unsuccessfully authenti-
cated, the TMP89FM42 goes into an idle state.
blank, and no password authentication is performed. To execute some special operation com-
mands, however, PNSA and PCSA are still required (a password string is not required) even if
a product is blank. In this case, the addresses defined in Table 22-21 must be selected as PNSA
and PCSA.
command.
cuted are as follows:
- Flash memory erase command (0xF0)
- Flash memory write command (0x30)
- Flash memory read command (0x40)
- RAM loader command (0x60)
- Flash memory security setting command (0xFA)
Because a password is created by using part of a user program, a special password setting
To cancel a password, Chip Erase (all erase) must be performed on flash memory. A pass-
If there is data other than 0xFF in any one byte of data written to the address 0xFFE0 through
If all data written to the address 0xFFE0 through 0xFFFF are 0xFF, a product is considered
Whether a product is blank or non-blank can be confirmed by executing the status output
The operation commands that require PNSA and PCSA (password string) for them to be exe-
Not required (notes 4 and 5)
0x8000 d PNSA d 0xFEFF
0x8000 d PCSA d 0xFEFF
Blank product (note 1)
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0x8000 d PCSA d 0xFF00 - N
0x8000 d PNSA d 0xFEFF
Non-blank product
Required (note 3)
8 d N
TMP89FM42