M16C62N Datasheet, PDF (204/213 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Mitsubishi microcomputers
M16C / 62N Group (80-pin)
Appendix Standard Serial I/O Mode 2 (Flash Memory Version) ^{SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER}
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.
RxD1
(M16C reception data)
TxD1
(M16C transmit data)
7516
Figure 1.32.31. 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.
RxD1
(M16C reception data)
TxD1
(M16C transmit data)
FA16
Data size (low)
Check
sum
Program ^Program
data
data
Data size (high)
Figure 1.32.32. Timing for download
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