Fujitsu FR20 User Manual
280
CHAPTER 21 Flash Memory
21.1
Overview of Flash Memory
The MB91F191A and MB91F192 devices have built-in flash memory that can erase all
sectors in a block and erase per sector using a single +3V power source, and write per
sectors in a block and erase per sector using a single +3V power source, and write per
half-word (16-bit) using a FR-CPU with 254-Kbyte
*1
(2-Mbit) / 384-Kbyte (3-Mbit)
capacities respectively.
■
Overview of Flash Memory
The function of this flash memory is the same as our 2Mbit (256K
× 8 / 128K × 16) flash memory
MBM29LV200T (excluding some sector configuration), and writing from outside the device using a
*2
,
ROM writer is also possible.
In addition to the MBM29LV200T equivalent function, if it is used as built-in ROM of the FR-CPU,
command/data reading per word (32-bit) is possible, and high-speed operation can be realized.
It is built-in flash memory of 3V operation 254 KByte
*1
(MB91F191A)/384 KByte (MB91F192).
Combining a flash memory macro and FR-CPU interface circuit realizes the following functions.
•
CPU program/data storage memory function
- When this flash memory is used as ROM, 32-bit bus width access is enabled.
- Enables reading, writing, and erasing (auto program algorithm
*3
) using the CPU
•
Functions equivalent to those of the MB29LV200T (a flash memory product)
- Enables reading, writing, and erasing (auto program algorithm
*3
) using the ROM writer
This chapter describes use of this flash memory from the FR-CPU. Refer to the separate manual for the
ROM writer User’s Guide for details when using this flash memory from the ROM writer.
*1: The MBM29LV200T has 256 Kbytes, but a 2-Kbyte area overlaps with built-in RAM for the
MB91F191A, so use is impossible.
*2: The memory capacity of the MB91F192 is 384 Kbytes, but it is extended to be based on the
MBM29LV200T (256 Kbytes), so the function is the same.
*3: Automatic program algorithm=Embedded Algorithm
TM
Embedded Algorithm
TM
is a registered trademark of Advanced Micro Devices, Inc.