Unconditional Test Mode Disable Seal - STMicroelectronics SPC572L series Reference Manual

RM0400
Optionally, the customer can create a password to enable manufacturer entry into test
mode.
31.7.1

Unconditional test mode disable seal

Warning:
The steps for unconditionally disabling test mode are the same steps required for
implementing passcode-protected entry into test mode with one exception—the passcode
specified must be one of the following three invalid passcodes:
•
0x0000_0000
•
0xFFFF_FFFF
•
0x5555_5555
To unconditionally disable test mode entry:
1. Select individual flash blocks to be protected by programming the appropriate values
into the Test Mode Disable Block Select Group A and Test Mode Disable Block Select
Group B areas shown in the UTEST flash memory map.
2. Program one of the three invalid passcodes shown above into the Test Mode Override
Passcode area shown in the UTEST flash memory map.
3. Program the value 0x2D3C_4B5A into the Test Mode Disable Seal location specified in
the UTEST flash memory map.
After the next reset is asserted, Test Mode is permanently disabled.
Note: Blocks selected for test mode disable can be selected in either or both Test Mode Disable
Block Select Groups (A and B) because those fields are logically ORed to determine the
blocks to be protected.
The lifecycle state must be programmed to 'Production at OEM' or later for the disable seal
to be in effect.
31.7.2 Passcode-protected test mode disable seal
The steps for implementing passcode-protected entry into test mode are the same required
for unconditionally disabling test mode with the exception that —the passcode specified
must NOT be one of the following three invalid passcodes:
• 0x0000_0000
•
0xFFFF_FFFF
• 0x5555_5555
To implement passcode-protected test mode entry:
This process is not reversible. After completing these steps
the SPC572Lx microcontroller is permanently prevented from
entering test mode for factory analysis.
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Flash Memory Programming and Configuration
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