
Functional Description and Application Information
32 kbyte Flash Module (S12SFTSR32KV1)
MM912F634
Freescale Semiconductor
269
4.36
32 kbyte Flash Module (S12SFTSR32KV1)
4.36.1
Introduction
This document describes the S12SFTSR32K module, that includes a 32 kbyte Flash (nonvolatile) memory.
CAUTION
A Flash block address must be in the erased state before being programmed. Cumulative
programming of bits within a Flash block address is not allowed, except for status field
updates required in EEPROM emulation applications.
The Flash memory is ideal for single-supply applications, allowing for field reprogramming without requiring external high voltage
sources for program or erase operations. The Flash module includes a memory controller that executes commands to modify
Flash memory contents.
Array read access time is one bus cycle for bytes and aligned words, and two bus cycles for misaligned words. For Flash memory,
an erased bit reads 1 and a programmed bit reads 0. It is not possible to read from a Flash block while any command is executing
on that specific Flash block.
4.36.1.1
Glossary
Command Write Sequence — A three step MCU instruction sequence to execute built-in algorithms (including program and
erase) on the Flash memory.
Flash Array — The Flash array constitutes the main memory portion of a Flash block.
Flash Block — An analog block consisting of the Flash array and Flash IFR with supporting high voltage and parametric test
circuitry.
Flash IFR — Nonvolatile information memory, consisting of 128 bytes, located in the Flash block outside of Flash main memory.
Refer to the SoC Guide on how to make the Flash IFR visible in the global memory map.
4.36.1.2
Features
32 kbytes of Flash memory comprised of one 32 kbyte block divided into 64 sectors of 512 bytes
Nonvolatile information memory (Flash IFR) comprised of one 128 byte block
Automated program and erase algorithm
Interrupt on Flash command completion, command buffer empty
Fast program and sector erase operation
Burst program command for faster Flash array program times
Flexible protection scheme to prevent accidental program or erase
Single power supply for all Flash operations including program and erase
Security feature to prevent unauthorized access to the Flash memory