Hi to all, I was going through the user manual of cortex-M3's LM3S1635. www.luminarymicro.com/.../LM3S1635.html. From that manual, Three fully programmable 16C550-type UARTs with IrDA support . So then i went Wikipedia to search about IrDA. It says that its an infrared protocol for up to few meters distance wireless communication.
But i dont know whats the use of IrDA in UART protocol and how we can use that IrDA visibly? whats the advantage over normal UART in Embedded system? since IrDA is a half duplex protocol, why we need to implement it on UART? why only on UART? Few examples pls and some clear details. To increase the speed of tx and RX data? Where else we are using that feature and for what?
... it's wireless!
If its simple wireless means at what frequency it transmits the data and receives?
So if cortex is a transmitter means at the receiver side should we have IrDA compatible device needed to make a communication?
"If its simple wireless means at what frequency it transmits the data and receives?"
Have you actually tried googling for "IrDA"?
en.wikipedia.org/.../Infrared_Data_Association
http://www.irda.org/
The "Ir" in "IrDA" stands for Infrared - because it uses Infrared light.
"So if cortex is a transmitter means at the receiver side should we have IrDA compatible device needed to make a communication?"
Yes, obviously, you need two IrDA-capable devices to make an IrDA communication!
I doubt very much that the Stellaris is just a transmitter, though? Surely it must also include a receiver?
Just as for RS232 you need an RS232 Transceiver to convert between the microcontroller's logic levels and the RS232 signals on the wire, so for IrDA you will require an IrDA Transceiver to convert between the microcontroller's logic levels and the IR light signals through the air.
eg, see: www.vishay.com/.../
With IrDA you could implement a PPP layer, and have your device connect to the Internet using your IrDA-capable mobile phone, but without connecting any cable between phone and your device.
Or you may use a IrDA-capable printer and print out reports, without connecting your device to the printer.
Since you don't seem to know much about IrDA, I assume that you are not interested in IrDA links. Then just ignore all paragraphs mentioning IrDA in the datasheet, and use the three UARTS as normal. It is quite common that microcontrollers contains a lot of nice extra features that you don't need to use.
Ya thank you for your reply. Yes i know that IR doesn't uses frequency. But i did asked that wrongly. But IR technology is an old technology right? why we need this still?
"IR doesn't uses frequency"
But of course it does!
"IR technology is an old technology right?"
So what?
Copper wires are an even older technology by far!
IR can give you a very simple - and, therefore cheap - wireless link.
"why we need this still?"
Well, obviously, you don't need it - so, as Per says, just don't worry about it!
I'm sure there are also plenty of other features of the Stellaris that you, personally, won't beed...