Writing To Otprom With Examples 3 And 4 - Intel 8XC196K Series User Manual

Send Comments (Example 4)
08 WRITE_WORD. Low word of DATA to PC location
005EH (contents of ADDR). Increment ADDR by
two.
12 GO. PUSHes the user PC onto the stack and
begins program execution at 0400H. (Had they
been changed, GO would also PUSH the PSW
and WSR.)
You can now interrogate memory locations using RISM commands. Reading location 80H using
the method shown in example 2 will return 1122H (the value that the executing program loaded
into that location). A REPORT command (14H) will place "01" into the DATA register, indicating
that a program is running. A HALT command (13H) will stop execution of the program. The PC
will be reset to the Monitor_Pause location. At this point, a REPORT command (14H) will place
"00" into the DATA register, indicating that the program is halted.
16.10.6.5

Writing to OTPROM with Examples 3 and 4

If a program writes to OTPROM or if it is to be loaded into an OTPROM location, +12.5 volts
must be applied to V
PP
Assume that the program in examples 3 and 4 attempted to write OTPROM location A500H with
the value 1122H. Changing the contents of location A500H alters any code programmed at
2500H because that location has been remapped to A500H. Any bits at 2500H that are zero can-
not be changed to one.
Assume that the program is loaded into OTPROM locations A000–A004H. Changing the con-
tents of those locations alters any code programmed at 2000–2004H because those locations have
been remapped to A000–A004H. Any bits in those locations that are zero cannot be changed to
one, so you may get unexpected results. (Internal RAM can always be altered to any value.)
. There are other considerations, as well.
PROGRAMMING THE NONVOLATILE MEMORY
DATA
00 5E
Memory Addresses
005F
04
00 5E
ADDR
04 00 00 5E
005E
00 00 60
04 00 00 60
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