Datasheet
Section 21 ROM (Mask ROM Version, H8S/2138 F-ZTAT, H8S/2134 F-ZTAT, and H8S/2132 F-ZTAT)
Rev. 4.00 Jun 06, 2006 page 580 of 1004
REJ09B0301-0400
21.4 Overview of Flash Memory
21.4.1 Features
The features of the flash memory are summarized below.
• Four flash memory operating modes
Program mode
Erase mode
Program-verify mode
Erase-verify mode
• Programming/erase methods
The flash memory is programmed 32 bytes at a time. Erasing is performed by block erase (in
single-block units). When erasing multiple blocks, the individual blocks must be erased
sequentially. Block erasing can be performed as required on 1-kbyte, 8-kbyte, 16-kbyte, 28-
kbyte, and 32-kbyte blocks.
• Programming/erase times
The flash memory programming time is 10 ms (typ.) for simultaneous 32-byte programming,
equivalent to 300 µs (typ.) per byte, and the erase time is 100 ms (typ.) per block.
• Reprogramming capability
The flash memory can be reprogrammed up to 100 times.
• On-board programming modes
There are two modes in which flash memory can be programmed/erased/verified on-board:
Boot mode
User program mode
• Automatic bit rate adjustment
With data transfer in boot mode, the bit rate of the H8S/2138 Group or H8S/2134 Group chip
can be automatically adjusted to match the transfer bit rate of the host.
• Protect modes
There are three protect modes, hardware, software, and error protect, which allow protected
status to be designated for flash memory program/erase/verify operations.
• Programmer mode
Flash memory can be programmed/erased in programmer mode, using a PROM programmer,
as well as in on-board programming mode.