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Thu, 04 Dec 2008 14:42:52 -0800 http://backend.userland.com/rss092 suppose in an industrial application we have to controll some events ,which are time dependent, using microcontroller.the problem is like : there are <noauthor@nospam.com> http://www.8051projects.net/forum-t10431.html Would the devices go off after 10s by themselves or does the micro have to switch them off after the time slot elapses? sashijoseph<sashijoseph@nospam.com> http://www.8051projects.net/forum-t10431.html hi caze,i don't see where you are having problem, can you be more clearArun Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t10431.html hi Cazehere comes the fundamental RTOS functionalities Semaphores mutex and mutual exclusion.by using one or more than one or all of the above techni shyam<shyam@nospam.com> http://www.8051projects.net/forum-t10431.html hi @ sashijoseph, devices has to be stoped by microcontroller itself. caze<rajeev.caze@nospam.com> http://www.8051projects.net/forum-t10431.html hi shyam, great idea. but i guess writing routine for 8051 will be too lengthy and tedious work .is it possible to caze<rajeev.caze@nospam.com> http://www.8051projects.net/forum-t10431.html yes it can be written u will find some keil examples with RTX51.a little effort and u can get the source of the kernel too ammend it according to shyam<shyam@nospam.com> http://www.8051projects.net/forum-t10431.html @CazeShyam's method is elegant and the correct way to go.But you could also use the 8051's 2 timers and 8 external timers(2xLM558) to control all 10 d sashijoseph<sashijoseph@nospam.com> http://www.8051projects.net/forum-t10431.html i feel its no more a challenge if we used external analog timers, in such case we don't need the micro at all because the input signals can trigger th Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t10431.html Arun Kumar V wrote ...3) wire External interrupt(EX0) pin to all the 10 inputs with help of diodes in such a way that when any of the 10 inputs are re Ajay<contact@nospam.com> http://www.8051projects.net/forum-t10431.html ^^but then which of the 10 inputs caused the interrupt wouldn't be traceable.I think that's why Arun has ORed the inputs to the INT pin(with diodes) a sashijoseph<sashijoseph@nospam.com> http://www.8051projects.net/forum-t10431.html I think that is a near perfect solution for the problem i woud say by arun. pdi33<islurpundalik@nospam.com> http://www.8051projects.net/forum-t10431.html hi @ arun , thanks a lot ....... and ill be so thankful to u if u can post asm program here . caze<rajeev.caze@nospam.com> http://www.8051projects.net/forum-t10431.html Sorry for late reply, was on a short trip.Thank you SJ and Pdi33 !caze - i'll post the asm code and schematic today Arun Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t10431.html hello caze,as promised here's my code and schematic, i have written for 8 I/Os your task is to further increase it to 10 I/Os (its easy after you go t Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t10431.html wow! how bout starting programming competetions?I am not sure how good it will be.. but its gonna be fun.. Ajay<contact@nospam.com> http://www.8051projects.net/forum-t10431.html Sure, Why not ?............... Arun Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t10431.html nice idea ajay, would really tickle our old grey cells.. and help a few newcomers in many ways.when do we start? pdi33<islurpundalik@nospam.com> http://www.8051projects.net/forum-t10431.html every competition needs a judge...i believe we can help each other out.. for sure...but to judge who is better wud not be that easy shyam<shyam@nospam.com> http://www.8051projects.net/forum-t10431.html wisely said shyam. hmmm, too many offtopic posts here i think. pdi33<islurpundalik@nospam.com> http://www.8051projects.net/forum-t10431.html Well..I have answer to that too Competitions will go like this..1. Problem will be post on forum and entries will be accepted till a fixed date2. Aft Ajay<contact@nospam.com> http://www.8051projects.net/forum-t10431.html that would be nice. but will it cover all possible forum topics ? AVR/8051/PIC/VB. i.e. will there be individual probems posted for each forum heading pdi33<islurpundalik@nospam.com> http://www.8051projects.net/forum-t10431.html Arun Kumar V wrote ...hello caze,as promised here's my code and schematic, i have written for 8 I/Os your task is to further increase it to 10 I/Os (i ijatorzaty<ijat.zaty@nospam.com> http://www.8051projects.net/forum-t10431.html @izator..,as u can see, arun has posted the most important part of ur assignment which is the principle of operation and hardware which is more than h pdi33<islurpundalik@nospam.com> http://www.8051projects.net/forum-t10431.html 10) the tick time of 50 msec can be reduced to say 20msec but to get 10 sec delay we would require to count 500 interrupts but the 8 bit counter can c Mr.Shabiul<hui_shyong@nospam.com> http://www.8051projects.net/forum-t10431.html well u thought of it right. but to generate a 30seconds tick (that is a very long time ), u may have to change the timer mode to 16 bits ( two bytes) pdi33<islurpundalik@nospam.com> http://www.8051projects.net/forum-t10431.html Arun Kumar V wrote ...hello caze,as promised here's my code and schematic, i have written for 8 I/Os your task is to further increase it to 10 I/Os (i Mr.Shabiul<hui_shyong@nospam.com> http://www.8051projects.net/forum-t10431.html pdi33 wrote ...well u thought of it right. but to generate a 30seconds tick (that is a very long time ), u may have to change the timer mode to 16 bit Mr.Shabiul<hui_shyong@nospam.com> http://www.8051projects.net/forum-t10431.html 5) in the timer0 ISR declare 10 counters (use registers/variables) check which flag/s is high( already set high in the Ex int.ISR), if a match is foun Mr.Shabiul<hui_shyong@nospam.com> http://www.8051projects.net/forum-t10431.html Hello Mr.shabiul,i feel you are trying to do too many things at the same time, pl. follow a step by step approach. the solution i offered here is fo Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t10431.html Arun Kumar V wrote ...Hello Mr.shabiul,i feel you are trying to do too many things at the same time, pl. follow a step by step approach. the solutio Mr.Shabiul<hui_shyong@nospam.com> http://www.8051projects.net/forum-t10431.html How to define others variables rather than R0-R7 in register banks 0and without using register banks 1becoz changing register banks looks complicated. Mr.Shabiul<hui_shyong@nospam.com> http://www.8051projects.net/forum-t10431.html Shabiul, may be you are forgetting the 256 bytes RAM on board 8052, declare Variables in RAM and In Assembly this is how it can be done: DSEG ORG 0 Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t10431.html why is FLAG_1 BIT 1 while COUNTER_1: DS 1?by the way, there is alot questions in the previous posts tat you din answer me...regarding checking the fla Mr.Shabiul<hui_shyong@nospam.com> http://www.8051projects.net/forum-t10431.html shabiul, you have edited your previous post after my reply ( see the time stamp, i replied at 11.15 pm and you modified your last reply after reading Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t10431.html i edit my post just because i got new question and i dun wan to double post.about ur question, Port1 means the whole port1.0-1.7, port pin 1.0 means o Mr.Shabiul<hui_shyong@nospam.com> http://www.8051projects.net/forum-t10431.html about ur question, Port1 means the whole port1.0-1.7, port pin 1.0 means only the pin.correct me if wrong.other way of putting it would be, port1.0 is Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t10431.html @ Mr.shabiul,I Bet even your College Professor wouldn't have explained the whole concept with such clarity as Arun did.so the least you can do is " Th nischay kumar<nischay.kumar@nospam.com> http://www.8051projects.net/forum-t10431.html Ya, i know moderators here are very nice and willing to help, tats why i stick to here.I keep refresh the page to see if they had replied me or not, b Mr.Shabiul<hui_shyong@nospam.com> http://www.8051projects.net/forum-t10431.html @Arunthanks, u explained very well n clear. I wonder why i just dun understand such a simple thing be4....anyway,I m still stuck in tis part 5) n 6)5) Mr.Shabiul<hui_shyong@nospam.com> http://www.8051projects.net/forum-t10431.html