Yung-Chieh Lo / F042K6_Flash

To access the internal flash of STM32F042K6.

This library provides a Partition class used to segment the STM32F042K6 internal flash so that the caller can read/write/erase the partition.

Examples

    FlashPartition config(0x7c00, 0x400);

    uint8_t buf[16];
    config.Read(address, buf, sizeof(buf));

    config.EraseAll();
    config.Write(address, buf, sizeof(buf));

f042k6_flash.cpp@1:7a490a05943a, 2017-09-11 (annotated)

Committer:
yjlou
Date:
Mon Sep 11 05:09:15 2017 +0000
Revision:
1:7a490a05943a
Parent:
0:a71e3b72379a 
Remove debug message.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
yjlou 0:a71e3b72379a 1 #include "f042k6_flash.h"
yjlou 0:a71e3b72379a 2
yjlou 0:a71e3b72379a 3 #include <string.h>
yjlou 0:a71e3b72379a 4
yjlou 0:a71e3b72379a 5 // Read flash content in this partition.
yjlou 0:a71e3b72379a 6 void FlashPartition::Read(uint32_t offset, char* buf, size_t len) {
yjlou 0:a71e3b72379a 7 memcpy(buf, (void*)(USER_FLASH_AREA_START + start_addr_ + offset), len);
yjlou 0:a71e3b72379a 8 }
yjlou 0:a71e3b72379a 9
yjlou 0:a71e3b72379a 10 // Write flash content into this partition.
yjlou 0:a71e3b72379a 11 // Returns true for success.
yjlou 0:a71e3b72379a 12 bool FlashPartition::Write(uint32_t offset, const char* buf, size_t len) {
yjlou 0:a71e3b72379a 13 UnlockControlRegister();
yjlou 0:a71e3b72379a 14
yjlou 0:a71e3b72379a 15 if (*REG32(FLASH_SR) & SR_BSY) {
yjlou 0:a71e3b72379a 16 return false;
yjlou 0:a71e3b72379a 17 }
yjlou 0:a71e3b72379a 18
yjlou 0:a71e3b72379a 19 *REG32(FLASH_CR) |= CR_PG;
yjlou 0:a71e3b72379a 20
yjlou 0:a71e3b72379a 21 const uint16_t* src = (uint16_t*)buf;
yjlou 0:a71e3b72379a 22 uint16_t* dst = (uint16_t*)(USER_FLASH_AREA_START + start_addr_ + offset);
yjlou 0:a71e3b72379a 23 for (int i = 0; i < (len + 1) / 2; i++) {
yjlou 0:a71e3b72379a 24 *(dst++) = *(src++);
yjlou 0:a71e3b72379a 25 while (*REG32(FLASH_SR) & SR_BSY);
yjlou 0:a71e3b72379a 26 }
yjlou 0:a71e3b72379a 27
yjlou 0:a71e3b72379a 28 *REG32(FLASH_CR) &= ~CR_PG;
yjlou 0:a71e3b72379a 29
yjlou 0:a71e3b72379a 30 return true;
yjlou 0:a71e3b72379a 31 }
yjlou 0:a71e3b72379a 32
yjlou 0:a71e3b72379a 33 // Erase whole partition
yjlou 0:a71e3b72379a 34 // Returns true for success.
yjlou 0:a71e3b72379a 35 bool FlashPartition::EraseAll() {
yjlou 0:a71e3b72379a 36 UnlockControlRegister();
yjlou 0:a71e3b72379a 37
yjlou 0:a71e3b72379a 38 if (*REG32(FLASH_SR) & SR_BSY) {
yjlou 0:a71e3b72379a 39 return false;
yjlou 0:a71e3b72379a 40 }
yjlou 0:a71e3b72379a 41
yjlou 0:a71e3b72379a 42 *REG32(FLASH_CR) |= CR_PER;
yjlou 0:a71e3b72379a 43
yjlou 0:a71e3b72379a 44 for (uint32_t page = USER_FLASH_AREA_START + start_addr_;
yjlou 0:a71e3b72379a 45 page < (USER_FLASH_AREA_START + start_addr_ + size_);
yjlou 0:a71e3b72379a 46 page += kFlashPageInBytes) {
yjlou 0:a71e3b72379a 47 *REG32(FLASH_AR) = page;
yjlou 0:a71e3b72379a 48 *REG32(FLASH_CR) |= CR_STRT;
yjlou 0:a71e3b72379a 49 while (*REG32(FLASH_SR) & SR_BSY);
yjlou 0:a71e3b72379a 50 }
yjlou 0:a71e3b72379a 51 *REG32(FLASH_CR) &= ~CR_PER;
yjlou 0:a71e3b72379a 52
yjlou 0:a71e3b72379a 53 return true;
yjlou 0:a71e3b72379a 54 }
yjlou 0:a71e3b72379a 55
yjlou 0:a71e3b72379a 56 void FlashPartition::UnlockControlRegister() {
yjlou 0:a71e3b72379a 57 if (*REG32(FLASH_CR) & CR_LOCK) {
yjlou 0:a71e3b72379a 58 *REG32(FLASH_KEYR) = 0x45670123;
yjlou 0:a71e3b72379a 59 *REG32(FLASH_KEYR) = 0xCDEF89AB;
yjlou 0:a71e3b72379a 60 }
yjlou 0:a71e3b72379a 61 }