Kakvo...
12 отговора
622 прегледа
Re: Kakvo...
FirmWare-ist - chovek koito programira na nisko nivo , kato izpulnimite programi ne vurvyat na nastolen komputar a na vgradeni integralni shemi - mikrokontroleri, procesori za vgrajdane v aparatura i t.n. Primer - programirane na procesora na GSM, programirane na mikrokontroleri. Naposleduk izlizat integrali shemi s vgradeni java interpretatori , napimer pishesh na java programa , koyato se izpalnyava da rechem ot ... tvoya hladilnik :)))...zabravih da spomena programite na komputrite na novite avtomobili i t.n. ... abe to ako trugna vsichko da izbroyavam :)).Primer za specializiran ezik za progtramirane e da kajem Step 7 na Siemens.
Kato kazvam "nisko nivo " nyamam predvid nepremenno programirane na asembler i podobni :) , za povecheto chipove ima C kompilatori , JAVA i t.n. Nyakoi firmi proizvoditelki razprostranyavat sobstveni kit-ove za razrabotka kum integralnite si shemi
Ako ti e interesno mojesh da si kupish za 10 lv edna integralna shema napr PIC16f84 i da se probvash ... ima si vsichko - procesor, pamet za danni i za programi, analogovi i cifrovi vhodove i izhodi ... be neshto kato malko PC za vgrajdane :)
Vaprosnata shema se izpolzva mnogo chesto za emulirane na SIM karti za telefoni, satelitni dekoderi i drugi podobni ... leleeee mai se otpleshah .... abe ako te interesuva neshto na temata shte ti dam mail :)
telecom project - mislya che e yasno - neshto v oblastta na telekomunikaciite :)))
RTOS = Real Time Operating Systems - OS, koito rabotyat v rejim na realno vreme.. t.e. nyamash vremedelene mejdu otdelni procesi kakto pri Win , RTOS se izpolzvat v kritichni sistemi , kadeto se iziskva nezabavna obrabotka na vhodni signali ( napr jivotopoddurjashti sistemi, navigaciya,komunikacii i dr podobni ) .Takiva OS garantirat che signala shte bude obraboten vednaga sled postupvaneto mu.
Dano da sum il polezen s mnogoslovieto si :))))
Kato kazvam "nisko nivo " nyamam predvid nepremenno programirane na asembler i podobni :) , za povecheto chipove ima C kompilatori , JAVA i t.n. Nyakoi firmi proizvoditelki razprostranyavat sobstveni kit-ove za razrabotka kum integralnite si shemi
Ako ti e interesno mojesh da si kupish za 10 lv edna integralna shema napr PIC16f84 i da se probvash ... ima si vsichko - procesor, pamet za danni i za programi, analogovi i cifrovi vhodove i izhodi ... be neshto kato malko PC za vgrajdane :)
Vaprosnata shema se izpolzva mnogo chesto za emulirane na SIM karti za telefoni, satelitni dekoderi i drugi podobni ... leleeee mai se otpleshah .... abe ako te interesuva neshto na temata shte ti dam mail :)
telecom project - mislya che e yasno - neshto v oblastta na telekomunikaciite :)))
RTOS = Real Time Operating Systems - OS, koito rabotyat v rejim na realno vreme.. t.e. nyamash vremedelene mejdu otdelni procesi kakto pri Win , RTOS se izpolzvat v kritichni sistemi , kadeto se iziskva nezabavna obrabotka na vhodni signali ( napr jivotopoddurjashti sistemi, navigaciya,komunikacii i dr podobni ) .Takiva OS garantirat che signala shte bude obraboten vednaga sled postupvaneto mu.
Dano da sum il polezen s mnogoslovieto si :))))
Re: basi mamata!
dobre de, kak na ezik JAVA (interpretator) ste "izklokvam" dannite kam nekakvo seriino ustroistvo, EEPROM da kajem?
sa varta cikli FOR ili kakto se kazvat tam v JAVA????
zasot podiavolite trebva da se pise na JAVA?????
kato tolkova vi marzi pisete na C, a samo po zapletenite mesta na ASSEMBLER?
sa varta cikli FOR ili kakto se kazvat tam v JAVA????
zasot podiavolite trebva da se pise na JAVA?????
kato tolkova vi marzi pisete na C, a samo po zapletenite mesta na ASSEMBLER?
в отговор на FullScream
#6
Re: Kakvo...
Izviniavam se za latinitzata, ama oshte ne sam si oformil XP-to
Ta misalta mi e, che NT e RTOS, vupreki vseobshtata zabluda. Protzes s prioritet "REALTIME_PRIORITY_CLASS" ima stepen na prioritet po-viskoka dori ot sistemnata. T.e. kogato raboti nishka na takuv protzes absoliutno nishto ne moje da ia prekusne.
Ta misalta mi e, che NT e RTOS, vupreki vseobshtata zabluda. Protzes s prioritet "REALTIME_PRIORITY_CLASS" ima stepen na prioritet po-viskoka dori ot sistemnata. T.e. kogato raboti nishka na takuv protzes absoliutno nishto ne moje da ia prekusne.
Re: Kakvo...
Не съм любител на Java , но имам идея кога е удачно да се пише на Java. В общия случай еди фърмуерист трябва да е повече инженер, отколкото програмист ... Java се учи доста по-бързо от C и е по-разбираема за "не програмисти".
За програмиста , естествено C и Асемблер ще са по-добри , защото и там те притискат бързодействие и памет (много повече от колкото при програмирането за настолни PC) .Но .... много малко програмисти разбират от електроника :)) ... т.е. много по-лесно е да научиш инженер на Java , от колкото да обучиш програмист на електроника.
Все пак 99 % от процесорите за вграждане в момента се програмират на Асемблер :)
За програмиста , естествено C и Асемблер ще са по-добри , защото и там те притискат бързодействие и памет (много повече от колкото при програмирането за настолни PC) .Но .... много малко програмисти разбират от електроника :)) ... т.е. много по-лесно е да научиш инженер на Java , от колкото да обучиш програмист на електроника.
Все пак 99 % от процесорите за вграждане в момента се програмират на Асемблер :)
RTOS
Windows 2000 and Real-Time Processing
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Deadline requirements, either hard or soft, characterize real-time environments. Hard real-time systems (for example, a nuclear power plant control system) have deadlines that the system must meet to avoid catastrophic failures such as loss of equipment or life. Soft real-time systems (for example, a car's fuel-economy optimization system) have deadlines that the system can miss, but timeliness is still a desirable trait. In real-time systems, computers have sensor input devices and control output devices. The designer of a real-time computer system must know worst-case delays between the time an input device generates an interrupt and the time the device's driver can control the output device to respond. This worst-case analysis must take into account the delays the operating system introduces as well as the delays the application and device drivers impose.
Because Windows 2000 doesn't prioritize device IRQs in any controllable way and user-level applications execute only when a processor's IRQL is at passive level, Windows 2000 isn't always suitable as a real-time operating system. The system's devices and device drivers—not Windows 2000—ultimately determine the worst-case delay. This factor becomes a problem when the real-time system's designer uses off-the-shelf hardware. The designer can have difficulty determining how long every off-the-shelf device's ISR or DPC might take in the worst case. Even after testing, the designer can't guarantee that a special case in a live system won't cause the system to miss an important deadline. Furthermore, the sum of all the delays a system's DPCs and ISRs can introduce usually far exceeds the tolerance of a time-sensitive system.
Although many types of embedded systems (for example, printers and automotive computers) have real-time requirements, the special embedded version of Windows NT (currently based on Windows NT 4 but eventually to be updated for a future version of Windows 2000) doesn't have real-time characteristics. It is simply a version of Windows NT that makes it possible, using system designer technology that Microsoft licensed from VenturCom, to produce small-footprint versions of Windows NT suitable for running on devices with limited resources. For example, a device that has no networking capability would omit all the Windows NT components, including network management tools and adapter and protocol stack device drivers, related to networking.
Still, there are third-party vendors that supply real-time kernels for Windows NT 4 and Windows 2000. The approach these vendors take is to embed their real-time kernel in a custom HAL and to have Windows 2000 or Windows NT 4 run as a task in the real-time operating system. The task running Windows 2000 or Windows NT serves as the user interface to the system and has a lower priority than the tasks responsible for managing the device. See VenturCom's Web site, [линк], for an example of a third-party real-time kernel extension for Windows NT or Windows 2000.
//// source - Inside Windows 2000 by David Solomon and Mark Russinovich
моя забележка: това че приоритетът e REALTIME_PRIORITY не значи чак толкова много. пак си има thread sheduling - кернелът изобщо няма и намерение да вдигне по този случай IRQL-то над IRQL DISPATCH_LEVEL.
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Deadline requirements, either hard or soft, characterize real-time environments. Hard real-time systems (for example, a nuclear power plant control system) have deadlines that the system must meet to avoid catastrophic failures such as loss of equipment or life. Soft real-time systems (for example, a car's fuel-economy optimization system) have deadlines that the system can miss, but timeliness is still a desirable trait. In real-time systems, computers have sensor input devices and control output devices. The designer of a real-time computer system must know worst-case delays between the time an input device generates an interrupt and the time the device's driver can control the output device to respond. This worst-case analysis must take into account the delays the operating system introduces as well as the delays the application and device drivers impose.
Because Windows 2000 doesn't prioritize device IRQs in any controllable way and user-level applications execute only when a processor's IRQL is at passive level, Windows 2000 isn't always suitable as a real-time operating system. The system's devices and device drivers—not Windows 2000—ultimately determine the worst-case delay. This factor becomes a problem when the real-time system's designer uses off-the-shelf hardware. The designer can have difficulty determining how long every off-the-shelf device's ISR or DPC might take in the worst case. Even after testing, the designer can't guarantee that a special case in a live system won't cause the system to miss an important deadline. Furthermore, the sum of all the delays a system's DPCs and ISRs can introduce usually far exceeds the tolerance of a time-sensitive system.
Although many types of embedded systems (for example, printers and automotive computers) have real-time requirements, the special embedded version of Windows NT (currently based on Windows NT 4 but eventually to be updated for a future version of Windows 2000) doesn't have real-time characteristics. It is simply a version of Windows NT that makes it possible, using system designer technology that Microsoft licensed from VenturCom, to produce small-footprint versions of Windows NT suitable for running on devices with limited resources. For example, a device that has no networking capability would omit all the Windows NT components, including network management tools and adapter and protocol stack device drivers, related to networking.
Still, there are third-party vendors that supply real-time kernels for Windows NT 4 and Windows 2000. The approach these vendors take is to embed their real-time kernel in a custom HAL and to have Windows 2000 or Windows NT 4 run as a task in the real-time operating system. The task running Windows 2000 or Windows NT serves as the user interface to the system and has a lower priority than the tasks responsible for managing the device. See VenturCom's Web site, [линк], for an example of a third-party real-time kernel extension for Windows NT or Windows 2000.
//// source - Inside Windows 2000 by David Solomon and Mark Russinovich
моя забележка: това че приоритетът e REALTIME_PRIORITY не значи чак толкова много. пак си има thread sheduling - кернелът изобщо няма и намерение да вдигне по този случай IRQL-то над IRQL DISPATCH_LEVEL.
в отговор на FullScream
#11
Utochnenie...
Otnosno RTOS: I tam si ima vremedelenie. Prosto tam e garantirano maksimalnoto vreme za izpalnenie na dadena operacia!!!