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???ü??: ??????????×÷??????uc/os??uclinux

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??°????ê?ú?????ú????????????it×é??????????????????????????????????ר????×÷????????·???????????????????????????????????????microsoft?????? wince??windriversystem??????vxworks??·?±???·????±?????±????????×÷???????ú±í???????????ú?·???ì??????·?°??ó????????°??????á?á???ú?·??±??????§?????ù????

uc/os??uclinux??×÷????????????????????????????±???·???????????·?????????×÷??????????×÷?????????±??×÷??????·????±??×÷????????·???±????¨???? uc/os??uclinux????±???·?????×??á??????????×÷???????????????????????????é????????????????·?????×÷????????????????

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uc/os??uclinux??×÷?????????±?°??????·?????????????·?????????????????????×÷??????uc/os???????????????????????????§?????????????????????±????????????????????????????×?????????±à????2k??uclinux?ò??????±ê×?linux ?????????????????????????í?÷???????è??????????×÷?????????????????????é???§???à??????????????·?????????±ê×?linux???é??????????????±à???ó??±ê??????????????°?k??????

uc/os????????·????????ú?????á??????????????°??á???±?????????±??×÷?????????????á???????÷???????í???±?????í???????????????¨???????????í??????·???????????

uclinux??????????????????linux°?±???uclinux??micro-conrol-linux??????????±ê×?linux?à±????ü??????±ê×?linux??×÷?????????¨???????ó???????????????????????????÷????????????????????mmu(???????í????)?????à???????????è?????¨??????

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????????×÷?????????????????????????????????¨???????????±????????????°??è??????????ר?????¨????????×÷?????????????¤×÷?? ?????÷?????????????§????????????????????????×÷??????????????×?????????????????????????????????????uc/os??uclinux????·???±?????


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?????÷????·???"°??á???÷??"??"·?°??á???÷??"?????ù±?·??????ù??"·?°??á???÷??"??????????????????±??÷?????????ò?????????±?????????±?????????á?????ò???????????ò×???·??úcpu????????×?????????cpu????·????????????????ù??"°??á???÷??"?????????????÷×??????????????¨?ü???????????ò?????????????????ú?????¨???±?????±??±?????°??á?±?°??????????(????·??????÷×???)??°?cpu·???????????????

×÷?????±??×÷??????uc/os??????????°??á?????±?à????????????°??á???????±???????????±?ò?????????÷????×?????????????????uc/os??×??à?????§??64 ????????·?±???????????0~63??????0??×????????????÷???¤×÷??????????·???????·???×????????????????°??????????????

??×????????????????°?????¨???¨?????÷????±í??????????uc/os???????????????????????????????????????????????????????étcb(task control block)?????á?????????????????±±???????±????????????????????????÷?????é?×????±??? ostcbhighrdy?????±?°×????????÷??????tcb???·?????ó?÷??os_task_sw() ????????????????????

uclinux???????÷????????linux???????????????????¨?±???????????????±?????ú?ú?ì?????????????±?????±?????????¨???÷??????(?¨?±?÷???í????)???¨?????????±?ò?????ü???±?????????ó?????à?????????????????¨?????????÷??fork ?????ú??×???????????????

uclinux????fork?÷???ê???ó??????×??????ú????????????(???±?????????? sleep)???±??×??????÷??exit???????????÷??exec???????????????????????±?ò?ú?ú????????????????????????????????????????????±?????????????????±??????±×?????????exit?òexec?ó??×?????????wakeup°??????????????????????????ù????????

uclinux????????mmu???í?????÷????????????·??????±???????ù?????ò??·????????·?????????????í???·????×÷??????????????????±??¤???÷???????????????í???????????????????è???????à?????±????????±??¤?????????????§???ò????????????????????????????????????????????±à???±???è???à??×?????·??ò???×????????±?????

??????·?????????????uc/os?????????????±?????????ó?è???????????à???ò?????????ú×??????????±?????ó????uclinux?ò???á??????????±ê×?linux???à????????·????????????????????í?÷?????????????????????????±???§???ò?è?????????????±??????????????????rt-linux???????????????????????????????±??????


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uc/os?????ò????????????????????????°ü??????????(???????????????????????????°?à??????)??±à???ó??uc/os????????6~10kb???ù??????±??í???????????????????§????????uc/os?????????????????????????è?????°????×???????????????????????

uclinux?ò????????linux?ê????????????????????????????romfs???????????????????????à??????°???ext2???????????ó?ü??????????????????????×???????·??????×???????§??romfs????????±??§??ext2?????????è???ü?????ú????????romfs?????????à???ò???????¨???????????????é(superblock)?è???ü??????????????romfs???????????§??????????±??????????????è??????±??????????????é??ram????·?·¨???????í(ram????????ext2????????)??

uclinux????????linux??????×÷??????????????????·?±????§????????????????????tcp/ip???é??????uclinux??·??????????è±??á????±?????

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(1)uc/os??????

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?¤???í?÷?§??×?????ram(??k×???)??×÷???à?????·????????????????

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?¤os_cpu.h???è???è????????????±ê?????????¤·??ò??

?¤os_cpu.h???è???ù?÷?????????????????????????????ê??

?¤os_cpu.h???è?????????????í?÷??×??¤?????¨?????????????à????

?¤os_cpu_a.asm?è??????4????±à????????????

?¤os_cpu_c.c?è????c????±à??6???ò????????

?¤?????÷?·????include.h????????????????????????×??????·??????????

(2)uclinux??????

????uclinux??????linux?????????????????????????????á??±??????????à?? uc/os??uclinux???????????????à????°???????????uclinux????±ê???í?÷???????ú×?????uc/os???ú×??????????????è??????×???????(??°?k×???????)????rom??ram??

uclinux???????ó??????·???3????????

?¤?á???????????????????????????í?÷???á?????????????????§???????í?÷?á?????ò?è??????linux/arch???????à?????í?÷?á??????????????uclinux?????ú?????ó??·????????????í?÷?????????á????????????×????????ú?????????¨???÷?????????????÷??±í?????ü???????????í?????????????????????¤???????????????????????????????????????????????ò????linux/arch/????????????linux?ù?§???????á???????à·±?à???ù????????????????????????????????????·??????à????????????±à????

?¤???¨?????????????????????????í?÷??????uclinux???§????????·??§???í?÷???ò?è?????à???????á?????????¨???à????????±à???à???ú??????mc68ez328?????ù????mmu??m68k???????????±???????è?????¨ linux/arch/m68knommu/platform/ mc68ez328????????????±à???ú×????ò(???????§???ò??????????????????????)???????????÷?????ò???ò???????????ò????

?¤°????????????????ù?????í?÷??±?uclinux?§?????°???????è??°???????????°????????è????linux/arch/?platform/???¨???????à??°??????????????????¨???à?????????ú??crt0_rom.s?òcrt0_ram.s???????è??????rom.ld?òram.ld??????????°?????????°ü?¨???????ò??±à?????·??±????è??????????

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?¨????uc/os??uclinux??±?????????????????????×÷??????????·????÷???????? uc/os?????????????????§?????????±?????????????????????í?÷???????à???ò????uclinux?ò?????????à?????ó?????±??????°????????????í?÷???????à??????????????uclinux???????à?????????????§??????????????tcp/ip???é???????è??linux·á????×???????????????????????uclinux?????à?±??????????cisco ?????? 2500/3000/4000 ?·???÷?????ù??uclinux??×÷??????·????? ×???????×÷???????????????????????????è?ó???¨?????ò????????????????????????????·?????uc/os?????????±??????????????????·?pda?????????????????????????????????òuclinux?????í????????