Otprom Memory Map - Intel 8XC196NT User Manual

8XC196NT USER'S MANUAL
mode, you can program and verify single or multiple words in the OTPROM. This is the
only mode that allows you to read the signature word and programming voltages and to
program the PCCBs and unerasable PROM (UPROM) bits. Programming vendors and Intel
distributors typically use this mode to program a large number of microcontrollers with a
customer's code and data.
•
Auto programming mode enables the 8XC196 device to act as a master to program itself
with code and data that reside in an external memory device. Using this mode, you can
program the entire OTPROM array except the UPROM bits and PCCBs. After
programming, you can use the ROM-dump mode to write the entire OTPROM array to an
external memory device to verify its contents. Customers typically use this low-cost method
to program a small number of microcontrollers after development and testing are complete.
•
Serial port programming mode enables you to download code and data (usually from a
personal computer or workstation) to an 8XC196 device (the slave) through the serial I/O
port. You can write data to the OTPROM asynchronously via the TXD (P2.0) pin and read
the data via the RXD (P2.1) pin. Customers typically use this mode to download large
sections of code to the microcontroller during software development and testing.
You can also program individual OTPROM locations without entering a programming mode.
With this method, called run-time programming, your software controls the number and duration
of programming pulses. Customers typically use this mode to download small sections of code to
the microcontroller during software development and testing.

15.2 OTPROM MEMORY MAP

The OTPROM contains customer-specified special-purpose and program memory (Table 15-1).
The 128-byte special-purpose memory partition is used for interrupt vectors, the chip configura-
tion bytes (CCBs), and the security key. Several locations are reserved for testing or for use in
future products. Write the value (20H or FFH) indicated in Table 15-1 to each reserved location.
The remainder of the OTPROM is available for code storage.
Address
Range
(Hex)
FF9FFF
Program memory
FF2080
FF207F
Reserved (each location must contain FFH)
FF205E
FF205D
PTS vectors
FF2040
†
Intel manufacturing uses this location to determine whether to program the OFD bit.
Customers with QROM or MROM codes who desire oscillator failure detection should
equate this location to the value 0CDEH.
15-2
Table 15-1. 87C196NT OTPROM Memory Map
Description