M16C/62 Group DATASHEET

CPU Rewrite Mode (Flash Memory Version)Mitsubishi microcomputersM16C / 62 GroupSINGLE-CHIP 16-BIT CMOS MICROCOMPUTERBlock Erase Command (2016/D016)By writing the command code “2016” in the first bus cycle and the confirmation command code “D016”in the second bus cycle that follows to the block address of a flash memory block, the system initiatesan auto erase (erase and erase verify) operation.Whether the auto erase operation is completed can be confirmed by reading the status register or theflash memory control register 0. At the same time the auto erase operation starts, the read statusregister mode is automatically entered, so the content of the status register can be read out. Thestatus register bit 7 (SR7) is set to 0 at the same time the auto erase operation starts and is returnedto 1 upon completion of the auto erase operation. In this case, the read status register mode remainsactive until the Read Array command (FF16) or Read Lock Bit Status command (7116) is written or theflash memory is reset using its reset bit.____The RY/BY status flag of the flash memory control register 0 is 0 during auto erase operation and 1when the auto erase operation is completed as is the status register bit 7.After the auto erase operation is completed, the status register can be read out to know the result ofthe auto erase operation. For details, refer to the section where the status register is detailed.Figure 1.29.5 shows an example of a block erase flowchart.Each block of the flash memory can be protected against erasure by using a lock bit. For details, referto the section where the data protect function is detailed.StartWrite 2016Write D016Block addressRY/BY status flag= 1?NOYESCheck full status checkBlock erasecompletedFigure 1.29.5. Block erase flowchart243