Could u please tell how to go about searching for such a board..a usb port would also be helpful
And you didn't even thought about telling what type of processor - architecture (ARM, 8051, ...) or size of processor or requirements for RAM, flash, supply voltage, ...
My guess is that you haven't spent any time at all looking yourself, since you haven't realized that you have to put down a longer list of requirements than just two seral ports and optionally a USB port (host or device? what speed? USB OTG?)
Well the problem is I can hardly find any boards with 2 serial ports, so I thought of narrowing it down after I have a list of all of them. I have thought of the LPC21xx series but I was wondering if there are other options, and the 2 serial ports is my most pressing requirement.
Just to clarify, all my other requirements are flexible, as of now. I am new to microcontrollers, this is just a hobby project. Is there a place that can give me boards with 2 serial ports, from which I can select the best one?
What, exactly, do you mean by "serial ports"?
I2C, SPI, CAN, etc, are all "serial"!
If you mean UART ports (ie, async serial), do you mean just logic level, or do you also need RS232 or RS485 or some other type of transceiver?
I suggest that you start here http://www.keil.com/dd/search_parm.asp to find a list of chips with two (or more) of your required type of "serial port" - and then Google for boards using those chips!
Sorry, I need two RS232 ports on the board.
Thanks for your reply Andy. That was exactly what I wanted.
If you can't find any suitable with two RS232 ports, logic-level-to-RS232 converter boards are readily (and quite cheaply) available (eg, ebay) - so you could use a board that just gives logic-level UART ports.
Note that quite a few boards provide one UART port with RS232 transceivers, and other UART(s) at logic levels.
Depending on your electronics/hardware skills, it's not that difficult to build your own logic-level-to-RS232 converter on a prototyping board.
eg, see: www.8052.com/.../176453
For communication with a PC, you can do away with the RS232 transceivers completely, and just use these:
www.8052.com/.../176460
I must be doing something wrong, but looking for Keil evaluation boards for ARM chips, I didn't had too hard a time to find boards with two RS232 ports (and 2 CAN ports, USB, ...) A quick look seems to indicate that MCB2100, MCB2130, MCB2140, MCB2300, MCBSTR7, MCBSTR730, MCBSTR750, ... could be used.
So you obviously haven't considered the Keil boards. That means that you have some hidden selection criteria that you haven't told us about yet.
That would be the cost. But no sweat, I found what I wanted, thanks!
See. You had "cost" as a selection criteria. Shouldn't you then also post the allowest price range when asking for help locating boards?
Price normally don't matter much when buying a single board for development. Maybe you are not looking for one board, but for a solution you can use in hundreds of installations? That would then also be information that you should have supplied in your initial post.