a1200是基于montavista公司经过裁减和优化过的mobilinux配合qte平台开发出来的linux手机。
基本硬件配置为:
CPU : intel xscale pxa270芯片，312mhz arm处理器，支持arm9汇编，arm32和thumb16指令集
用户可用flash ：11.5m
存储卡：支持如下存储卡
SYN 1401A 32 MB microSD/TransFlash
SYN 1402A 64 MB microSD/TransFlash
SYN 1403A 128 MB microSD/TransFlash
SYN 1404A 256 MB microSD/TransFlash
SYN 1405A 512 MB microSD
SYN 1406A 1 GB microSD
其它可以兼容的microSD 内存卡：
Kingmax 64MB，Kingmax 128MB 和Toshiba 256MB
注：SanDisk Ultra II. Mobile microSD. 内存卡与本手机存在兼容问题，不建议使用。
内存：通过telnet连接到a1200手机，然后运行如下命令会发现：
# cat /proc/meminfo
total: used: free: shared: buffers: cached:
Mem: 47452160 46338048 1114112 0 2535424 26181632
Swap: 0 0 0
MemTotal: 46340 kB
MemFree: 1088 kB
MemShared: 0 kB
Buffers: 2476 kB
Cached: 25568 kB
SwapCached: 0 kB
Active: 24232 kB
Inactive: 15432 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 46340 kB
LowFree: 1088 kB
SwapTotal: 0 kB
SwapFree: 0 kB
Committed_AS: 41004 kB
这里每个参数的具体含义如下（图省事，贴了部分meminfo的英文说明）：
MemTotal: Total usable ram (i.e. physical ram minus a few reserved
bits and the kernel binary code)
MemFree: The sum of LowFree HighFree
Buffers: Relatively temporary storage for raw disk blocks
shouldn't get tremendously large (20MB or so)
Cached: in-memory cache for files read from the disk (the
pagecache). Doesn't include SwapCached
SwapCached: Memory that once was swapped out, is swapped back in but
still also is in the swapfile (if memory is needed it
doesn't need to be swapped out AGAIN because it is already
in the swapfile. This saves I/O)
Active: Memory that has been used more recently and usually not
reclaimed unless absolutely necessary.
Inactive: Memory which has been less recently used. It is more
eligible to be reclaimed for other purposes
HighTotal:
HighFree: Highmem is all memory above ~860MB of physical memory
Highmem areas are for use by userspace programs, or
for the pagecache. The kernel must use tricks to access
this memory, making it slower to access than lowmem.
LowTotal:
LowFree: Lowmem is memory which can be used for everything that
highmem can be used for, but it is also availble for the
kernel's use for its own data structures. Among many
other things, it is where everything from the Slab is
allocated. Bad things happen when you're out of lowmem.
SwapTotal: total amount of swap space available
SwapFree: Memory which has been evicted from RAM, and is temporarily
on the disk
Dirty: Memory which is waiting to get written back to the disk
Writeback: Memory which is actively being written back to the disk
Mapped: files which have been mmaped, such as libraries
Slab: in-kernel data structures cache
CommitLimit: Based on the overcommit ratio ('vm.overcommit_ratio'),
this is the total amount of memory currently available to
be allocated on the system. This limit is only adhered to
if strict overcommit accounting is enabled (mode 2 in
'vm.overcommit_memory').
The CommitLimit is calculated with the following formula:
CommitLimit = ('vm.overcommit_ratio' * Physical RAM) Swap
For example, on a system with 1G of physical RAM and 7G
of swap with a `vm.overcommit_ratio` of 30 it would
yield a CommitLimit of 7.3G.
For more details, see the memory overcommit documentation
in vm/overcommit-accounting.
Committed_AS: The amount of memory presently allocated on the system.
The committed memory is a sum of all of the memory which
has been allocated by processes, even if it has not been
"used" by them as of yet. A process which malloc()'s 1G
of memory, but only touches 300M of it will only show up
as using 300M of memory even if it has the address space
allocated for the entire 1G. This 1G is memory which has
been "committed" to by the VM and can be used at any time
by the allocating application. With strict overcommit
enabled on the system (mode 2 in 'vm.overcommit_memory'),
allocations which would exceed the CommitLimit (detailed
above) will not be permitted. This is useful if one needs
to guarantee that processes will not fail due to lack of
memory once that memory has been successfully allocated.
PageTables: amount of memory dedicated to the lowest level of page
tables.
VmallocTotal: total size of vmalloc memory area
VmallocUsed: amount of vmalloc area which is used
VmallocChunk: largest contigious block of vmalloc area which is free
vga : 240x320的触摸屏，色深为packed 18bpp格式
注意，packed 18bpp是对应着16bpp像素格式定义（rgb565）：
rrrrrggg gggbbbbb
这里的packed 18bpp的像素格式定义为（rgb666）：
000000rr rrrrgggg ggbbbbbb
还有一种与24bpp像素格式兼容的aligned 18bpp格式，像素定义为（rgb666）：
00rrrrrr 00gggggg 00bbbbbb
也有如下定义的格式：
rrrrrr00 gggggg00 bbbbbb00
天知道为什么moto要采用18bpp，或许这和intel的pxa270片子对液晶屏幕的驱动
电路有关，反正这样18bpp也是用了3个字节保存一个像素，那么干嘛不采用
aligned 18bpp呢？又可以和24bpp像素格式兼容，速度又快。这一点，很多人
都不理解，我也是做了两个多小时的试验，才试出来。让人发疯的moto。
声音 ：采用16位pcm码流直接播放，支持两种采样率8khz和44.1khz，这点编写
mp3播放器的朋友需要特别注意。
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