M30620FCAFP datasheet(283/615 Pages) RENESAS

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Appendix Standard Serial I/O Mode 2 (Flash Memory Version)

Mitsubishi microcomputers

M16C / 62A Group

SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

1-264

Lock Bit Disable Command

This command disables the lock bit. The command code “7516” is sent with the 1st byte of the serial

transmission. This command only disables the lock bit function; it does not set the lock bit itself.

However, if an erase command is executed after executing the lock bit disable command, “0” (locked)

lock bit data is set to “1” (unlocked) after the erase operation ends. In any case, after the reset is

cancelled, the lock bit is enabled.

Figure 1.29.32. Timing for disabling the lock bit

Download Command

This command downloads a program to the RAM for execution. Execute the download command as

explained here following.

(1) Transfer the “FA16” command code with the 1st byte.

(2) Transfer the program size with the 2nd and 3rd bytes.

(3) Transfer the check sum with the 4th byte. The check sum is added to all data sent with the 5th

byte onward.

(4) The program to execute is sent with the 5th byte onward.

When all data has been transmitted, if the check sum matches, the downloaded program is executed.

The size of the program will vary according to the internal RAM.

Figure 1.29.33. Timing for download

7516

RxD1

TxD1

(M16C reception data)

(M16C transmit data)

FA16

Program

data

Program

data

Data size (high)

Data size (low)

Check

sum

RxD1

TxD1

(M16C reception data)

(M16C transmit data)

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