Datasheet

Section 7 ROM
Rev. 1.50 Sep. 18, 2007 Page 105 of 584
REJ09B0240-0150
Section 7 ROM
The features of the 128-kbyte flash memory in this LSI are summarized below.
• Programming/erasing methods
 The flash memory is programmed 128 bytes at a time. Erasure is performed in single-block
units. The flash memory is configured as follows: four 1-kbyte blocks, one 28-kbyte block,
and three 32-kbyte blocks. To erase the entire flash memory, each block must be erased in
turn.
• Reprogramming capability
 The flash memory can be reprogrammed up to 1,000 times.
• On-board programming
 On-board programming/erasing can be done in boot mode, in which the boot program built
into the chip is started to erase or program of the entire flash memory. In normal user
programming mode, individual blocks can be erased or programmed.
• Programmer mode
 Flash memory can be programmed/erased in programmer mode using a PROM
programmer, as well as in on-board programming mode.
• Automatic bit rate adjustment
 For data transfer in boot mode, this LSI's bit rate can be automatically adjusted to match
the transfer bit rate of the host.
• Programming/erasing protection
 Sets software protection against flash memory programming/erasing.
• Power-down mode
 Operation of the power supply circuit can be partly halted in subactive mode. As a result,
flash memory can be read with low power consumption.