
520
15.4
Overview of Flash Memory
15.4.1
Features
The H8S/2214 has 128 kbytes of on-chip flash memory. 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 128 bytes at a time. Block erase (in single-block units) can
be performed. To erase multiple blocks, each block must be erased in turn. In block erasing, 1-
kbyte, 8-kbyte, 16-kbyte, 28-kbyte, and 32-kbyte block units can be set as required.
Programming/erase times
The flash memory programming time is T.B.D ms (typ.) for simultaneous 128-byte
programming, equivalent to T.B.D s (typ.) per byte, and the erase time is T.B.D ms (typ.).
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 LSI’s bit rate can be automatically adjusted to match the
transfer bit rate of the host.
Flash memory emulation in RAM
Flash memory programming can be emulated in real time by overlapping a part of RAM onto
flash memory.
Protect modes
There are two protect modes, hardware and software, 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.