HD6412340 HITACHI [Hitachi Semiconductor], HD6412340 Datasheet - Page 563

• Manufacturer Part Number: HD6412340
• Description: H8S/2345 F-ZTAT Hardware Manual
• Manufacturer: HITACHI [Hitachi Semiconductor]

17.6
17.6.1
The features of the flash memory are summarized below.
Four flash memory operating modes
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 (5 V version)
The flash memory programming time is 10 ms (typ.) for simultaneous 32-byte programming,
equivalent to 300 s (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:
Automatic bit rate adjustment
With data transfer in boot mode, the bit rate of the H8S/2345 Series chip can be automatically
adjusted to match the transfer bit rate of the host. (9600 bps, 4800 bps)
Flash memory emulation by RAM
Part of the RAM area can be overlapped onto flash memory, to emulate flash memory updates
in real time.
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.
Program mode
Erase mode
Program-verify mode
Erase-verify mode
Boot mode
User program mode
Overview of Flash Memory
Features
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