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22. Serial PROM Mode
22.12 Security
TMP89FM42
RA002
22.12.3Option codes
If a specified option code is placed at a specified address inside the interrupt vector area, whether password
string authentication is performed or not when executing the flash memory erase command and whether the
security program is checked or not when starting OCD can be designated.
- Erase password free code EPFC_OP (0xFFFA)
If changes are frequently made to a program during software development, there are cases in which
a password may get lost. In this case, you can cancel the password string authentication of the flash
memory erase command (0xF0) by setting the erase password free code (EPFC_OP). EPFC_OP is
assigned to 0xFFFA in the vector area. Allocate 0xFF to this EPFC_OP to cancel the password string
of the flash memory erase command (0xF0).
It is recommended that the password string authentication of the flash memory erase command
(0xF0) be enabled during mass production by allocating data other than 0xFF to EPFC_OP.
Only Chip Erase can cancel the password string authentication by using the flash memory erase
command. If Sector Erase is executed with EPFC_OP set to 0xFF, the TMP89FM42 goes into an idle
state. Commands other than the flash memory erase command cannot cancel the password string
authentication.
- OCD security program free code DAFC_OP (0xFFFB)
With the TMP89FM42, you can enable the security program to prevent illegal access attempts by a
third party. If the security program is enabled, restrictions are imposed on operation commands
related to memory access, and the startup of OCD.
The security program should be usually enabled at the time of shipment. If there is the possibility
that the OCD may be used by keeping the contents of memory intact, it is possible to directly start the
OCD by setting the OCD security program free code (DAFC_OP) and thereby skipping the security
program check (the password string authentication, however, is still required).
DAFC_OP is assigned to 0xFFFB in the vector area. To skip the security program check at the
startup of the OCD, assign 0xFF to DAFC_OP. In this case, the security program check is not per-
formed, and the OCD can be started by performing only the password string authentication.
If DAFC_OP is not 0xFF, whether the OCD can be used or not is determined by the status of the
security program. If the OCD is started with the security program enabled, the TMP89FM42 stops
communication and goes into an idle state. To use the OCD when the TMP89FM42 is in this idle
state, Chip Erase must be executed for flash memory by using the flash memory erase command
(0xF0). If the security program is disabled, the OCD can be started by performing only the password
string authentication.
Table 22-22 Option Codes
Symbol
Function
Address
Set value
EPFC_OP
Password string authentication when the flash
memory erase command is executed
0xFFFA
0xFF : The password string authentication is
skipped (only PNSA and PCSA are authenticated).
Other than 0xFF: The password string, PNSA, and
PCSA are authenticated.
DAFC_OP
Security program check when the OCD is
started
0xFFFB
0xFF: The security program check is skipped.
Other than 0xFF: The security program check is per-
formed.
Содержание TLCS-870/C1 Series
Страница 1: ...8 Bit Microcontroller TLCS 870 C1 Series TMP89FM42 查询TMP89FM42供应商 捷多邦 专业PCB打样工厂 24小时加急出货 ...
Страница 3: ...Revision History Date Revision 2007 10 25 1 First Release 2007 11 3 2 Contents Revised ...
Страница 4: ......
Страница 14: ......
Страница 18: ...1 3 Block Diagram TMP89FM42 1 3 Block Diagram Figure 1 2 Block Diagram ...
Страница 22: ...1 4 Pin Names and Functions TMP89FM42 ...
Страница 60: ...2 CPU Core 2 5 Revision History TMP89FM42 ...
Страница 76: ...3 Interrupt Control Circuit 3 8 Revision History TMP89FM42 ...
Страница 86: ...4 External Interrupt control circuit 4 3 Function TMP89FM42 ...
Страница 102: ...7 Voltage Detection Circuit 7 5 Revision History TMP89FM42 ...
Страница 126: ...8 I O Ports 8 3 I O Port Registers TMP89FM42 Note 2 i 0 to 1 ...
Страница 136: ...8 I O Ports 8 5 Revision History TMP89FM42 ...
Страница 142: ...9 Special Function Registers 9 3 SFR3 0x0E40 to 0x0EFF TMP89FM42 ...
Страница 146: ...10 Low Power Consumption Function for Peripherals TMP89FM42 ...
Страница 149: ...TMP89FM42 11 3 Revision History Rev Description RA001 Deleted SLEEP2 description ...
Страница 150: ...11 Divider Output DVO 11 3 Revision History TMP89FM42 ...
Страница 220: ...15 Real Time Clock RTC 15 4 Real Time Clock Operation TMP89FM42 ...
Страница 250: ...16 Asynchronous Serial Interface UART 16 15 Revision History TMP89FM42 ...
Страница 302: ...18 Serial Bus Interface SBI 18 7 Revision History TMP89FM42 ...
Страница 336: ...21 Flash Memory 21 4 Toggle Bit D6 TMP89FM42 Note 1 Make sure that you set the C register to 0x00 LD FLSCR2 0xD5 ...
Страница 338: ...21 Flash Memory 21 4 Toggle Bit D6 TMP89FM42 ...
Страница 384: ...22 Serial PROM Mode 22 15 Revision History TMP89FM42 ...
Страница 388: ...24 Input Output Circuit 24 1 Control Pins TMP89FM42 ...
Страница 404: ...25 Electrical Characteristics 25 11 Revision History TMP89FM42 ...
Страница 406: ...26 Package Dimensions TMP89FM42 ...
Страница 408: ......