FUJITSU MB91F109 FR30 - Manual (Page 376)

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CHAPTER 16 FLASH MEMORY
16.1 Outline of Flash Memory
This device type has an internal flash memory of 254 kilobytes (2 megabits) that
enables to perform the following functions with a single +3 V power supply:
simultaneous erasure of all sectors, erasure in sector units, and writing in half-word
(16 bits) units via the FR-CPU.
The flash memory employed here is basically the same as the Fujitsu 2-megabit (254
kilobits × 8 or 127 kilobits × 16) flash memory MBM29LV200T (except for a part of the
sector configuration) and enables writing with a device-external ROM writer.
When this memory is used as FR-CPU internal ROM, it becomes possible to read
instructions and data in word units (32 bits), in addition to features equivalent to the
features of the MBH29LV200. This enables high-speed device operation.
Along with this manual, refer to the MBM29LV200T/200B-10/12/15 Data Sheet.
■ Outline of Flash Memory
The employed flash memory is an internal 254-kilobyte flash memory operated at 3 V.
The following features are implemented by combining flash memory macros and FR-CPU
interface circuits:
❍ Features for use as CPU memory, for storing programs and data
• Accessibility through 32-bit bus when used as ROM
• Allowing read, write, and erase (automatic program algorithm*
1
) by the CPU
❍ Features of a single flash memory product equivalent to MBM29LV200T
• Allowing read or write (automatic program algorithm *
1
) by a ROM writer
*1: Automatic program algorithm: embedded algorithm
TM
■ Flash Memory Registers
Figure 16.1-1 shows the flash memory register.
Figure 16.1-1 Flash Memory Registers
0007C0 H
bit 7 0
Flash memory status register FSTR