Datasheet
Section 21 Flash Memory 
R01UH0310EJ0500 Rev. 5.00    Page 1123 of 1384 
Sep 25, 2012     
H8S/2426, H8S/2426R, H8S/2424 Group 
(10)  Erasure 
Erasure is performed with the erasure selection and block erasure command. 
Firstly, erasure is selected by the erasure selection command and the boot program then erases the 
specified block. The command should be repeatedly executed if two or more blocks are to be 
erased. Sending a block-erasure command from the host with the block number H'FF will stop the 
erasure operating. On completion of erasing, the boot program will wait for selection of 
programming or erasing. 
The sequences of the issuing of erasure selection commands and the erasure of data are shown in 
figure 21.13. 
Transfer of erasure 
program
Host Boot program
Preparation for erasure (H'48)
ACK
Erasure
Erasure (Erasure block number)
Erasure (H'FF)
ACK
ACK
Repeat
Figure 21.13 Erasure Sequence 










