Datasheet

681
Section 22 256kB Flash Memory (F-ZTAT)
22.1 Features
This LSI has 256 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 32 bytes at a time. Block erase (in single-block units) can be
performed. Block erasing can be performed as required on 1 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, this 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.