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Thu, 08 Jan 2009 09:48:31 -0800 http://backend.userland.com/rss092 I would like to use a transmitter to transmit the attendance collected by system to a remote pc instead directly using rs232 connectr.The remote compu <noauthor@nospam.com> http://www.8051projects.net/forum-t11856.html RS485 . .It is successor of RS232 and can cover distance upto 1200 to 1400 meters.I request Arun Kumar to further help you on this... say2paul<say2paul@nospam.com> http://www.8051projects.net/forum-t11856.html well i dont know ...but can RS485 be used commercially ... is it open source... i am talking about the networking protocol ahead of RS485! shyam<shyam@nospam.com> http://www.8051projects.net/forum-t11856.html Don't know buddy, but Arun recommended me the same..So lets wait for his reply! say2paul<say2paul@nospam.com> http://www.8051projects.net/forum-t11856.html what Arun recommended u was make ur own RS485 protocol!but i want to know if RS485 protocols like siemens MODBUS etc.. are open source and can be use shyam<shyam@nospam.com> http://www.8051projects.net/forum-t11856.html Hello Vaibhav, your thread says "RFID" and in your post you ask " transmit wireless using RS232" ?anyway i'll brief you how its done : RFID reader Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t11856.html Sorry for the delayed post and thanks alot for earlier replies!Now, let me explain u what i would like to do:1.I want to do project RFID attendane giv ramdasi vaibhav<ramdasivaibhav@nospam.com> http://www.8051projects.net/forum-t11856.html well thinking about your requirement, i would just answer for point 2,3,4well its possible to transmit data wirelessly to remote PC but distance is th Ajay<contact@nospam.com> http://www.8051projects.net/forum-t11856.html Thank you ajay sir for your reply.Your suggestion of LAN is appreciable but my guide insisted me to use wireless transmission.Also my classroom hasn't ramdasi vaibhav<ramdasivaibhav@nospam.com> http://www.8051projects.net/forum-t11856.html Dear Arun, I never used RF transceivers. So I was bit curious for the security thing in RF transmission.I mean to say that is the data we transmit usi say2paul<say2paul@nospam.com> http://www.8051projects.net/forum-t11856.html Hello vaibhav, RS232 can be used with help of 433Mhz RF modules ( range 300 meters in open air) for longer range ( as in your case) you have to go fo Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t11856.html Thank u arun sir.I think 433mhz module will do for range of 120meters,won't it? ramdasi vaibhav<ramdasivaibhav@nospam.com> http://www.8051projects.net/forum-t11856.html What is RFID MIFARE,say2paul,will u plz explain it? ramdasi vaibhav<ramdasivaibhav@nospam.com> http://www.8051projects.net/forum-t11856.html To make it simple for you..MIFARE card is fundamentally just a memory storage device, where the memory is divided into segments and blocks with simple say2paul<say2paul@nospam.com> http://www.8051projects.net/forum-t11856.html You could encrypt the data you transmit,for security.A lil extra work for the micro,that's all.We even have such a project in the download section. sashijoseph<sashijoseph@nospam.com> http://www.8051projects.net/forum-t11856.html @paul I mean to say that is the data we transmit using RF transmitter protected by a password..?to ensure the data transmitted is protected, we can u Arun Kumar V<nura1002003@nospam.com> http://www.8051projects.net/forum-t11856.html better use a short range RFID.. you can enclose the reader in a box with appropriate distance, students have to present the card and ofcourse that wil Ajay<contact@nospam.com> http://www.8051projects.net/forum-t11856.html i have some faqs regarding rfid attndance project:1. I wouid lik to know crystal clr working of circuit and the diff devices used. e.g. RFID reader, ramdasi vaibhav<ramdasivaibhav@nospam.com> http://www.8051projects.net/forum-t11856.html 4.What if a student wears more than one tag? Should i use high power (or freq ?..plz clr this pt i 've doubt here) rfid reader for this ? thanks in a ramdasi vaibhav<ramdasivaibhav@nospam.com> http://www.8051projects.net/forum-t11856.html RFID systems are typically short range.Usually the more secure the system, the shorter the range to preventeavesdropping.For Mifare cards 10cm is a lo ExperimenterUK<abx1717@nospam.com> http://www.8051projects.net/forum-t11856.html Does reader detect tags around certain area of coil only? This is vital bcz i want it should detect tags of those students present in the class or sit ramdasi vaibhav<ramdasivaibhav@nospam.com> http://www.8051projects.net/forum-t11856.html well that is understandable but the thing is.. it create chances of false attendance in our language we call it proxy i hope you are getting my poin Ajay<contact@nospam.com> http://www.8051projects.net/forum-t11856.html Well your suggestion is good and practical too,but i want to reduce the time required to take attendance during each lecture....That means there is no ramdasi vaibhav<ramdasivaibhav@nospam.com> http://www.8051projects.net/forum-t11856.html it takes not more than a second to mark successful attendance. I thnk just concentrate on your project implementation, later on you can find ways to a Ajay<contact@nospam.com> http://www.8051projects.net/forum-t11856.html Well,my project review and seminar is going to happen within few days.Plz help me . I wouid lik to know crystal clr working of circuit and the diff de ramdasi vaibhav<ramdasivaibhav@nospam.com> http://www.8051projects.net/forum-t11856.html