80C32-16 TEMIC Semiconductors, 80C32-16 Datasheet - Page 9

• Manufacturer Part Number: 80C32-16
• Description: CMOS 0 to 44 MHz Single Chip 8bit Microntroller
• Manufacturer: TEMIC Semiconductors

Rev. G (14 Jan. 97)
80C52 with Secret ROM
TEMIC offers 80C52 with the encrypted secret ROM
option to secure the ROM code contained in the 80C52
microcontrollers.
The clear reading of the program contained in the ROM
is made impossible due to an encryption through several
random keys implemented during the manufacturing
process.
The keys used to do such encryption are selected
randomwise and are definitely different from one
microcontroller to another.
This encryption is activated during the following phases :
– Everytime a byte is addressed during a verify of the
– MOVC instructions executed from external program
– EA is sampled and latched on reset, thus all state
For further information please refer to the application
note (ANM053) available upon request.
MATRA MHS
ROM content, a byte of the encryption array is
selected.
memory are disabled when fetching code bytes from
internal memory.
modification are disabled.
80C52 with Secret TAG
TEMIC offers special 64-bit identifier called “SECRET
TAG” on the microcontroller chip.
The Secret Tag option is available on both ROMless and
masked microcontrollers.
The Secret Tag feature allows serialization of each
microcontroller
equipment. A unique number per device is implemented
in the chip during manufacturing process. The serial
number is a 64-bit binary value which is contained and
addressable in the Special Function Registers (SFR) area.
This Secret Tag option can be read-out by a software
routine and thus enables the user to do an individual
identity check per device. This routine is implemented
inside the microcontroller ROM memory in case of
masked version which can be kept secret (and then the
value of the Secret Tag also) by using a ROM Encryption.
For further information, please refer to the application
note (ANM031) available upon request.
for
80C32/80C52
identification
of
a
specific
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