MB90670/675 Series
23
s PROGRAMMING TO THE ONE-TIME PROM ON THE MB90P673/P678
The MB90P673 and MB90P678 has a PROM mode for emulation operation of the MBM27C1000/1000A, to
which writing codes by a general-purpose ROM writer can be done via a dedicated adapter. Please note that
the device is not compatible with the electronic signature (device ID code) mode.
1.
Writing Sequence
The memory map for the PROM mode is shown as follows. Write option data to the option setting area according
by referring to “7. PROM Option Bit Map”.
Write data to the one-time PROM microcontrollers according to the following sequence.
(1) Set the PROM programer to select the MBM27C1000/1000A.
(2) Load the program data to the ROM programer address *1 to 1FFFFH. To select a PROM option, load the
option data from 00000H to 0002CH referring to “7. PROM Option Bit Map”.
(3) Set the chip to the adapter socket and load the socket to the ROM programer. Make sure that the device
and adapter socket are properly oriented.
(4) Program from 00000H to 1FFFFH.
Notes:
In mask-ROM products, there is no PROM mode and it is impossible to read data by a ROM programer.
Contact sales personnel when purchasing a ROM programer.
2.
Program Mode
In the MB90P673/P678, all the bits are set to “1” upon shipping from FUJITSU or erasing operation. To write
data, set desired bit selectively to “0”. However it is impossible to write electronically to the bits.
Note: The ROM image size for bank 00 is 48 Kbytes (ROM image for between FF4000H to FFFFFFH).
Type
Address*1
Address*2
Number of bytes
MB90P673
14000H
FF4000H
48 Kbytes
MB90P678
10000H
FF0000H
64 Kbytes
FFFFFFH
010000H
004000H
000000H
Address*2
Address*1
1FFFFFH
00000H
0002CH
Normal operation mode
PROM mode
Program area
(PROM)
Program area
(PROM)
ROM image
Option
setting area