Hi, i'm currently doing a project related to home automation. i need to control relays with my 8051. for wireless communication i decided to use XBEE PRO but unfortunately i couldn't get it. can anyone tell me any alternative like RF module?? its number, range etc. please mention most common modules if you can... thanx.
You are aware, that a common module in China need not be common in US? And "common" doesn't mean that it is a good choice for you.
You haven't even informed us about your exact range needs, and if you need a two-way link. Or if the module should be dumb and require addressing, validation, retransmission, ... handling by the processor or if the module should perform some or all of these things. Support for point-to-point or broadcast? 3.3V digital logic level? Or 5V? Or maybe RS-232 levels? Allowed frequency band to communicate on? One-off design or high-volume runs with availability important for many years? Single-frequency or wide-spectrum with some resilience to jamming in noisy environments? Energy-efficient for battery use? Built-in antenna or connector for external antenna? Possibility to power off transmitter while receiver still listens? Required supply voltage? Required temperature range? Special approvals? Frequencies etc configurable by software or hard-coded or unconfigurable?
okay i agree with low details thing. i need a power efficient module with 30m range at least better need 100m. point to point is optional i can use broadcast but if it comes there is no harm. RS-232 must be there as i need to hook up with 8051. frequency range is not my concern i only need acknowledgement mechanism and it should be handled by the module. XBEE PRO was my priority but i can have them due to unavailability of these modules in my region. can i have an alternative to it??? chip intena is preferable.
Interesting sentence: "RS-232 must be there as i need to hook up with 8051."
You mean that modules having a raw logic-level UART interface can't be used? Modules are normally not RS-232 if intended for connection directly to a microcontroller - RS-232 is normally for connecting to a PC or similar that have an _external_ serial port.
Next thing - there are modules that are using other interfaces, like SPI. They also work well with a 8051 chip.
If you have issues with getting XBee Pro modules in your region, then you should probably look for Bluetooth modules with RS-232 or logic-level UART interface. There are many other module types too, but an open issue then would be the frequency bands they use, in relation to the powers and frequencies allowed where you are. And many modules do not contain any acknowledge functionality.
yeah sorry about RS-232 what i meant was UART Interface. anyway thanx for the information :) its really helpful. i think m getting close to my solution :)
to go to digikey.com and search for "RF transceiver", not that I necessarily would buy there (although I often do) but I have found digikey to be an excellent "google" for parts.
Erik
Why not just use the real Google?!
Or why not just look in the catalogues of suppliers in your area?
Or why not just look in the catalogues of suppliers in your area? the real google gives a lot of non-part responses the digikey link to the datasheet is to the manufacturer the digikey 'google' give (reference) prices the real google does not have parametric search .....
the catalogues of suppliers in your area is plural, digikey is singular
But he's going to have to end up with those catalogues anyhow to see which one(s) he can actually get
with those catalogues anyhow to see which one(s) he can actually get with brands and partnumbers is a whole lot easier than "going in blind"
another thing is that the "general search" may have revealed a desirable feature that the device in catalog #1 do not have.
is he? why? is the law now requiring him to have to get them?
How else is he going to determine which ones are actually available to him?
as you suggested yourself, google is an option (along with alternative search providers).
But Google (et al) won't (necessarily) show what's actually available to him through the channels that he will actually use - hence the need to consult actual "catalogues" to verify actual availability.
Note that, in his opening post, he had identified a module - but said he "couldn't get it". Hence I conclude that a key part of the question is not just to identify any module, but specifically ones that are available to him through whatever (uspecified) channels that he uses...
hence the need to consult actual "catalogues" to verify actual availability.
rarely do cataloges show what is actually available in actual real time!