Datasheet
Section 21 Flash Memory 
R01UH0310EJ0500 Rev. 5.00    Page 1085 of 1384 
Sep 25, 2012     
H8S/2426, H8S/2426R, H8S/2424 Group 
21.3.1  User Programming Mode 
In the user programming mode, the flash memory can be programmed by the CPU through 
execution of software commands. In this mode, the user ROM and data flash can be programmed 
without using a ROM programmer with the microcomputer mounted on a system board. 
The programming and block erase commands should be executed only in each block area of the 
user ROM and data flash. 
The user programming mode provides the erase/write 0 mode (EW0 mode). Table 21.4 gives an 
overview of the EW0 mode specifications. 
Table 21.4  EW0 Mode Specifications 
Item Description 
Operating mode 
•  Single-chip mode 
•  On-chip ROM enabled expanded mode 
Area for storing the programming 
control program 
User ROM 
Area for executing the 
programming control program 
The programming control program should be transferred to an 
area outside the flash memory (such as RAM) before 
execution*
2
Programmable area  User ROM, data flash 
Limitations on software 
commands 
None 
Mode after programming or 
erasure 
Read status register mode 
CPU state during automatic 
programming or erasure 
Operating*
1
Flash memory status detection 
•  Reading the FMPRSF and FMERSF bits in FLMSTR by a 
program. 
•  Executing a read status register command to read the SR7, 
SR5, and SR4 bits in the status register. 
Notes:  1.  Make sure that no interrupt (except NMI) or DMA transfer is generated. 
  2.  In the user programming mode, the programming control program should be executed 
in the on-chip RAM or an external area. 










