Embedded Flash Memory (Flash) For Category 3 Devices; Introduction; Flash Main Features - ST STM32G4 Series Reference Manual

Embedded Flash memory (FLASH) for category 3 devices

3 Embedded Flash memory (FLASH)
for category 3 devices
3.1

Introduction

The Flash memory interface manages CPU AHB ICode and DCode accesses to the Flash
memory. It implements the erase and program Flash memory operations and the read and
write protection mechanisms.
The Flash memory interface accelerates code execution with a system of instruction
prefetch and cache lines.
3.2

FLASH main features

•
Up to 512 Kbyte of Flash memory with dual bank architecture supporting read-while-
write capability (RWW).
•
Flash memory read operations with two data width modes supported:
–
–
•
Page erase, bank erase and mass erase (both banks)
Flash memory interface features:
•
Flash memory read operations
•
Flash memory program/erase operations
•
Read protection activated by option (RDP)
•
4 Write protection areas (2 per bank when DBANK=1 and 4 for full memory when
DBANK=0)
•
2 proprietary code read protection areas (1 per bank when DBANK=1, 2 for all memory
when DBANK=0)
• 2 Securable memory areas defined by option (1 per bank when DBANK = 1, 1 for all
memory when DBANK = 0).
•
Prefetch on ICODE
•
Instruction Cache: 32 cache lines of 4 x 64 or 2 x 128 bits on ICode (1 KB RAM)
•
Data Cache: 8 cache lines of 4 x 64 bits or 2 x 128 on DCode (256B RAM)
•
Error Code Correction ECC: 8 bits per 64-bit double-word
–
–
•
Option byte loader
• Low-power mode
90/2083
Single bank mode DBANK=0: read access of 128 bits
Dual bank mode DBANK=1: read access of 64 bits
DBANK=1: 8 + 64 = 72 bits, 2 bits detection, 1 bit correction
DBANK=0: (8+64) + (8+64) = 144 bits, 2 bits detection, 1 bit correction
RM0440 Rev 1
RM0440