M30620FCAFP datasheet(225/274 Pages) MITSUBISHI

225 / 274 page

CPU Rewrite Mode (Flash Memory Version)

Mitsubishi microcomputers

M16C / 62A Group

SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

225

n = FE16

Start

Write 4116

n = 0

Write address n and

data n

RY/BY status flag

= 1?

Check full status

Page program

completed

n = n + 2

YES

Figure 1.26.4. Page program flowchart

Page Program Command (4116)

Page program allows for high-speed programming in units of 256 bytes. Page program operation

starts when the command code “4116” is written in the first bus cycle. In the second bus cycle through

the 129th bus cycle, the write data is sequentially written 16 bits at a time. At this time, the addresses

A0-A7 need to be incremented by 2 from “0016” to “FE16.” When the system finishes loading the data,

it starts an auto write operation (data program and verify operation).

Whether the auto write operation is completed can be confirmed by reading the status register or the

flash memory control register 0. At the same time the auto write operation starts, the read status

status register bit 7 (SR7) is set to 0 at the same time the auto write operation starts and is returned to

1 upon completion of the auto write operation. In this case, the read status register mode remains

active until the Read Array command (FF16) or Read Lock Bit Status command (7116) is written or the

flash memory is reset using its reset bit.

____

The RY/BY status flag of the flash memory control register 0 is 0 during auto write operation and 1

when the auto write operation is completed as is the status register bit 7.

After the auto write operation is completed, the status register can be read out to know the result of the

auto write operation. For details, refer to the section where the status register is detailed.

Figure 1.26.4 shows an example of a page program flowchart.

Each block of the flash memory can be write protected by using a lock bit. For details, refer to the

section where the data protect function is detailed.

Additional writes to the already programmed pages are prohibited.

M30620FCAFP Datasheet(PDF) 225 Page - Mitsubishi Electric Semiconductor