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Section 18 ROM
18.2
Overview of Flash Memory
18.2.1
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. The
block to be erased can be specified by setting the corresponding bit. There are block areas of
32KB × 3 blocks, 28KB × 1 block, and 1KB × 4 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 H8/3067's bit rate can be automatically adjusted to match
the transfer bit rate of the host (9600 bps and 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.
• PROM mode
Flash memory can be programmed/erased in PROM mode, using a PROM programmer, as
well as in on-board programming mode.
• 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.
Rev. 4.00 Jan 26, 2006 page 608 of 938
REJ09B0276-0400
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