Palm OS 為何不提供multitask API的解答

Luzofan

在kodak AMX的FAQ上, 有這樣一段文字:
  
The Palm, Inc. PalmOS does not provide access to the underlying AMX 68000 Multitasking Kernel. Instead, it provides a preconfigured collection of AMX tasks and AMX compatible device drivers which manage the Palm device. The PalmOS then provides an application API which offers the range of services needed by most developers to extend the functionality of the Palm device into a particular application area. The Palm Software Development Kit and related GNU or CodeWarrior tools are used to generate such Palm applications.
  
In some cases, third party developers take the Palm one step further. They license the Palm technology (hardware and/or software) from Palm, Inc. in order to create Palm-like devices but with different physical characteristics. Usually such devices bring new technology and interfaces into the Palm. Since the AMX license only permits AMX to be distributed in executable form, the technology licensed from Palm, Inc. will NOT include AMX and its application interface.
  
If the developer needs to use AMX services and create AMX compatible device drivers, then that developer must license AMX 68000 from KADAK Products Ltd. The developer then has full rights (without royalties) to link an application which includes AMX, the components (if any) licensed from Palm, Inc. and the developer's own software. The Symbol 1740 handheld scanner is one such example; the Handspring Visor is another.
  
If you wish to access AMX within one of these enhanced Palm-like devices, the licensing goes one step farther. For example, to create a new multi-threaded application based on the Symbol 1740 handheld scanner, you would need an AMX 68000 license AND access to both the Symbol and Palm, Inc. software in the Symbol product.
  
也就是說, 您要是想發展多工程式, 請逕行向kadak再購買一個AMX的授權.  
想當年, palm還沒成氣候的時候, 也沒料想到日後會成為一方之霸. 反而躲在palm OS後面的AMX, 才真正讓palm目前有了目前尾大不掉的局面.
  

jyeh

Hi  
請問您他們的網站是在那呢?
  
[quote]Luzofan wrote:
在kodak AMX的FAQ上, 有這樣一段文字:

Checko

其實要實際考慮是否需要Mutli Tasking,在Palm這麼少的Memory和不甚快的CPU上要作MutliTasking是很浪費的,而且依照當時Palm的設計目的,好像也沒有
MultiTask的需要,所以.....這可能是原因吧...

Luzofan

要找相關網站請您把一段內容貼到google去找大概就找得到, 反正是在kodak.com裡面某處便是了.
  
若以一般embedded OS的標準來說, 33mhz馬力已非常猛, 66mhz算是"超豪華配備"了. 當然若架上PALM OS的各種service便很難說結果如何.
  
我玩過acer的@vis機, 那是EZ+multitasking, 在切換程式時是會delay一點點. 有點像以前clie切高畫質後那種delay感覺, 但大致上來說還可以接受.
  
畢竟時代在進步, 在現在的一些應用來說, 沒有multitasking便等於斷手斷腿. 例如若裝上msn與icq連著bluetooth的gprs, 難道就必須一直停在某個ap裡嗎? 還有聽MP3等, multitasking都有其必要性.

chenkl

我不太懂PALM的程式設計，所以如果說錯了請大家包涵
  
以前在用DOS的時候也是單工作業，可是還是有很多的TSR程式如防毒軟體，Sidekick等
用起來也覺得很方便，在PALM上面也是類似，所需要的只是能告知有外來的事件
然後再切到那個AP去（像是ICQ有人發MESSAGE，PALM嗶一聲，再切到ICQ去用）
這應該在單工的環境就可以完成了吧
至於MP3，像CLIE一樣交給專用晶片去處理就好了啊

Luzofan

ICQ 在online時, 我想有可能已經是在多工狀態作業了. 不然前景程式在作業時, 是誰在處理packet呢? 當然也有可能是以TSR的方式, 每個packet近來都呼叫icq去處理. 但這不是很蠢嗎...
況且, palm os的tcp/IP stack本來就是在amx的多工模式下作業的.
  
我沒用clie聽過mp3. 但我沒記錯的話, clie好像在聽mp3時不能執行其他程式, 多工作業就可以消除這類的不方便.

matika

用Clie聽音樂時, 要勾選"enable background playback"
就可同時做別的事了 ~~