关于sx1内部记忆体容量的说明

wzb2005

4.3 RAM
16Mbytes of 70ns SRAM are integrated in Siemens SX1. This RAM is used by the application CPU and as a result is also shared by the applications and the Symbian OS.
RAM is visible for applications in the form of stack and heap spaces. The maximum stack and heap size is limited for each new process: around 2MB heap and 8K stack. This maximum is independent of the number of threads used. While a stack is allocated statically during initialization, the heap space is managed dynamically and starts with a minimum value. It is very important to keep in mind that the maximum heap size is only reached in very few cases. Applications are informed if memory resources are low. However, the system can close any application if it does not react to low memory warnings and continue to allocate memory.
There is no backup power supply for the RAM and the content will be lost if the device is switched off.
4.4 Flash ROM
Siemens SX1 uses flash ROM to store the system operating software and the user data, which should be retained in power-off states.
Flash ROM is divided into several areas and mapped to logical drives. Some of these are read-only; some have write permission. Symbian OS, Series 60 as well as most of the embedded applications reside on the "Z" drive. The flash ROM area of the "Z" drive supports the "execute-in-place" (XIP) feature. This allows system applications to be executed directly from the ROM address space. Other drives currently do not support XIP. All applications installed on any of these drives have to be loaded into RAM first and then executed. This fact should be considered by developers when designing the application runtime.
4.5 File system
The sections below provide information about the drives and files systems in the Siemens SX1, which can be used by 3rd-party applications. The data on any other drives should not be used or manipulated by 3rd-party applications. The content and the structure of this data can be changed without notice.
4.5.1 C drive
The C drive is read/write and located in flash ROM. This drive contains all user data as well as system and application data files. The content of the drive is retained if the device is switched off, though it can be re-initiated by the user via the "restore factory defaults" option in the system setup.
The total size of the drive is 4 Mbytes. Some 1.5 Mbytes are usually allocated by system applications, user PIM data as well as by a small number of sound and picture files.
Applications should not use or manipulate system data files, which are not documented in the SDK. The content and the structure of this data can be changed without notice. A good way to avoid this type of problem is to use documented APIs and avoid accessing the files directly.
The C drive is mapped to a directory in the PC file system in the emulator.
4.5.2 D drive
The D drive is a read/write virtual RAM drive. This drive contains temporary application and system data. The drive is re-initialized each time the device is powered on. The content of the drive is lost each time the device powers off.
The drive is allocated dynamically depending on current allocation requests. This is why the size of the allocated space is always about the same as the total size of the drive. Nevertheless, the maximum size of the drive is also limited by the size of the free RAM.
Siemens SX1 Technical Note for Application Developers Copyright ? 2003 Siemens AGAll rights reserved-10-
Information and Communication Mobile Hardware details for application developers Since the D drive resides in RAM, file read and write operations have a maximum speed in comparison to other drives. Applications should always use this drive for intensive file and caching operations. In some cases it may even make sense to create and write to a file on the D drive and, as soon as it is ready, to copy it to the C drive for permanent storage.
The D drive is mapped to a directory in the PC file system in the emulator.
4.5.3 E drive
The E drive is mapped to the MMC card and can contain arbitrary user data as well as installed applications and midlets.
The total and allocated sizes of the E drive correspond to the allocation of the MMC card being used. Application developers should be aware that their applications could be installed on the MMC card, which can be removed and may be replaced at any later time.
The E drive is mapped to a directory in the PC file system in the emulator.

wzb2005

大侠来看看：
里面明明写着16mb，为什么我在程式管理里面看到的总共容量只有4mb??
不明白！！

diarylist

那个16M指的是D盘，RAM（关机则存储信息消失），动态存储空间，又由于开机之后会占去一部分，所以一般我们看到的在8M左右。
你说的4M是C盘，ROM（关机之后存储信息也不会消失的）。一般用来放一些系统必备的文件，比如通讯录之类的。

希望可以解答你的疑惑

wzb2005

谢谢diarylist大侠的解答！
补丁打到哪里呢？

wzb2005

还有SX1的操作系统放在哪个盘？平时大家所指的升级内存是升级哪个盘呢？？

diarylist

补丁是打到Z盘和A盘，至于操作系统在哪个盘，我个人理解是在Z盘。
“平时说的升级内存",我好像没听说过升级内存这个说法

85543923

补丁是打到Z盘和A盘，至于操作系统在哪个盘，我个人理解是在Z盘。
“平时说的升级内存",我好像没听说过升级内存这个说法

wzb2005

SX1的电路图都有XD搞到了，还有的说要升级内存呢，期待~~

wzb2005

终于明白了，谢谢~~

kaneyet

不知道有没有将D盘改到E盘呢～？～～？～？

wzb2005

电路图下了，没有热风焊台呀，软件呢，先好好研究一下电路
能加大内存就好了~~~

yong_shan

ddddd，学知识！·

mondaysky

原帖由 wzb2005 于 2006-1-18 23:33 发表
SX1的电路图都有XD搞到了，还有的说要升级内存呢，期待~~

如果可以升级内存，那我们的SX1就值钱了！
呵呵………………

wzb2005

一定可以的，继续努力~~

windwalls

SX1内部所有的存储器如下：
1、SDRAM也就是动态RAM,大小16Mbytes，因为开机后被操作系统和应用程序占用一部分，所以程序管理器里显示D盘只有8M左右
2、Flash 1, 大小16Mbytes，包括Z1和Z2，也就是刷机时左边那一列显示的那样。
3、Flash2，大小8Mbytes，包括iboot，rolf，lffs。
其实flash1和flash2是从外面看是一个芯片，它是用stack技术把两个flash叠加到一起的，就是两个flash用不同的片选信号来区分罢了。
4、Egold，大小8Mbytes，其实是给SX1上的基带处理器（baseband processor PMB7850）用的，其实这个芯片也是stack的，不过它是和一个1Mbytes的SRAM，也就是静态RAM，叠加到一起的。这是SX1上的外接的所有存储器，当然不包括片内的和MMC卡。

wzb2005

又学到不少~~

wzb2005

如果换上更大的内存块，还要更改些什么呢？？

windwalls

可能软件需要打些补丁，硬件除了内存芯片，什么也不需要改了

xswry

谢谢diarylist大侠的解答！