# S3c2440

**Repository Path**: leonwey/S3c2440

## Basic Information

- **Project Name**: S3c2440
- **Description**: 基于S3C2440开发的项目
- **Primary Language**: C
- **License**: LGPL-3.0
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2017-12-04
- **Last Updated**: 2020-12-19

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# S3c2440
基于S3C2440开发的项目

汇编语言中
    ldr r0,=label
    ldr r0,label
有何区别？
    =加载到r0中的是标签的地址
    直接加载标签，相当于是将相对地址中数据加载到内存，基于PC

HARDWARE_ADDRESS
LED1~LED4-->GPB5~GPB8,低电平时,对应的灯亮
需配置为输出接口，低电平打开LED灯
KEY1-->EIN19-->GPG11,配置为输入或者中断方式
KEY2-->EINT11-->GPG3,配置为输入或者中断方式
KEY3-->EINT2-->GPF2,配置为输入或者中断方式
KEY4-->EINT0-->GPF0,配置为输入或者中断方式

nGCS0--->外接NORFLASH芯片(SST39VF1601/EN29LV160)的芯片引脚*CE
nGCS1--->未接
nGCS2--->未接
nGCS3--->网卡
nGCS4--->未接
nGCS5--->未接

nGCS6--->SDRAM的LnSCS0引脚
nGCS7--->未接

一共8个BANK
    BANK0~BANK5 位SRAM,ROM
    BANK6固定起始地址，SDRAM ,ROM,SRAM等
    BINK7可变的存储器 Bank 起始地址并 Bank 大小可编程
BANK上电默认禁止WAIT

问题：
    (1) ARM C库启动过程关于数据拷贝到底干了什么？
            只拷贝了RW,ZI区域还是拷贝了所有区域的数据？
关于MMU
    (1) 需要实验MMU映射的区域到底能不能包含所有的内存

ARM920T--MMU

The MMU is controlled from a single set of two-level page tables
stored in main memory, that are enabled by the M bit in CP15 register 1, providing a single address translation and protection scheme. You can independently lock and flush
the instruction and data TLBs in the MMU.

1MB(section),64KB(large Page),4KB(Small page),1KB(Tiny Page)

64 entry instruction TLB and 64 entry data TLB

16 domains implemented in hardware

invalidate whole TLB, using CP15 register 8
// meaning ????
independent lockdown of instruction TLB and data TLB, using CP15 register 10.
// meaning ???
hardware page table walks //遍历二级地址变换页表，查找对应的物理地址



Writing to Register 8 causes the MMU to perform a
TLB operation, to manipulate TLB entries. 

复位时，MMU被关闭
不存在内存映射， 


c_cpp_prperties include 备份
    win32:
                //"C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/*",
                //"C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/atlmfc/include/*",
                //"C:/Program Files (x86)/Windows Kits/10/Include/10.0.10586.0/um",
                //"C:/Program Files (x86)/Windows Kits/10/Include/10.0.10586.0/ucrt",
                //"C:/Program Files (x86)/Windows Kits/10/Include/10.0.10586.0/shared",
                //"C:/Program Files (x86)/Windows Kits/10/Include/10.0.10586.0/winrt",
    win64:
                //"C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/*",
                //"C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/atlmfc/include/*",
                //"C:/Program Files (x86)/Windows Kits/10/Include/10.0.10586.0/um",
                //"C:/Program Files (x86)/Windows Kits/10/Include/10.0.10586.0/ucrt",
                //"C:/Program Files (x86)/Windows Kits/10/Include/10.0.10586.0/shared",
                //"C:/Program Files (x86)/Windows Kits/10/Include/10.0.10586.0/winrt",

scatter_load()主要完成ZI区域数据的初始化