IC89E54 Datasheet, PDF (19/36 Pages) Integrated Circuit Solution Inc – 8-BITS SINGLE MICROCONTROLLER with 16/32/64-Kbytes of FLASH, 256 byte +512 byte RAM

IC89E54/58/64
FLASH MEMORY PROGRAMMING
The Flash architecture of IC89E54/58/64 is shown in Figure 13. IC89E54/58 include block 1 and lock bits block. The
signature bytes are fixed value reside in MCU, they are read only. Block 2 resides in IC89E64 only.
0030H _{3x8 bits}
Signature Bytes
0032H
0000H
3FFFH
16K Flash
( Block 1)
Dummy Address
0030H _{3x8 bits}
Signature Bytes
0032H
0000H
32K Flash
( Block 1)
7FFFH
Dummy Address
0030H _{3x8 bits}
Signature Bytes
0032H
0000H
60K Flash
( Block 1)
EFFFH
F000H
FFFFH
4K Flash
( Block 2)
3 Lock Bits Flash Cell
IC89E54
3 Lock Bits Flash Cell
IC89E58
3 Lock Bits Flash Cell
IC89E64
Figure 13. The Flash Architecture of IC89E54/58/64
EXTERNAL HOST MODE
The IC89E54/58/64 provide the user with a direct flash memory access that can be used for programming into the flash
memory without using the CPU. The direct flash memory access is entered using the External Host Mode. While the reset
input (RST) is continually held active (high), if the PSEN pin is forced by an input with low state, the device enters the External
Host Mode arming state at this time. The CPU core is stopped from running and all the chip I/O pins are reassigned and
become flash memory access and control pins. At this time, the external host should initiate a “Read Signature Bytes”
operation. After the completion of the “Read Signature Bytes” operation, the device is armed and enters the External Host
Mode. After the device enters into the External Host Mode, the internal flash memory blocks are accessed through the re-
assigned I/O port pins by an external host, such as a printed circuit board tester, a PC controlled development board or an
MCU programmer.
Integrated C ircuitSolution Inc.
19
MC012-0C 11/16/2001