HD64F3048VTF8 Datasheet, PDF (622/903 Pages) Renesas Technology Corp – Hardware Manual Renesas 8-Bit Single-Chip

Section 18 ROM (H8/3048F-ONE: Single Power Supply, H8/3048B Mask ROM Version)
Start
Set pins to boot program mode and execute reset-start
Host transfers data (H'00) continuously at prescribed
bit rate
H8/3048F-ONE measures low period of H'00 data
transmitted by host
H8/3048F-ONE calculates bit rate and sets value in bit
rate register
After bit rate adjustment, H8/3048F-ONE transmits one
H'00 data byte to host to indicate end of adjustment
Host confirms normal reception of bit rate adjustment
end indication (H'00), and transmits one H'55 data byte
After receiving H'55, H8/3048F-ONE transmits one
H'AA byte to host
Host transmits number of programming control program
bytes (N), upper byte followed by lower byte
H8/3048F-ONE transmits received number of bytes to
host as verify data (echo-back)
n=1
Host transmits programming control program
sequentially in byte units
H8/3048F-ONE transmits received programming
control program to host as verify data (echo-back)
n+1→n
Transfer received programming control program to
on-chip RAM
No
n = N?
Yes
End of transmission
Check flash memory data, and if data has already been
written, erase all blocks
Confirm that all flash memory data has been erased*
Check ID code at beginning of user program transfer
area
(Match)
Transmit one H'AA byte to host
Execute programming control program transferred to
on-chip RAM
(Mismatch)
Transmit H'FF as
error notification
Note: * If a memory cell does not operate normally and cannot be erased, one H'FF byte is transmitted as an erase error
indication, and the erase operation and subsequent operations are halted.
Figure 18.8 Boot Mode Execution Procedure
Rev. 3.00 Sep 27, 2006 page 594 of 872
REJ09B0325-0300