I bought a new Arduino Duemilanove and have built a number of simple circuits using the serial monitor via the Arduino's USB port to test and debug my circuits and programs.
Now I want to use an Arduino to control a serial modem through the digital pins 0/RX and 1/TX along with a MAX232 voltage level conversion circuit. Can I still use the serial monitor for debugging and testing? Or is there a conflict if I try to use the USB port for the serial monitor at the same time that I am sending/receiving data through digital pins 0/1 ?
If there IS a conflict, then what's the best way to debug a circuit that uses the digital pins 0/1 for RX/TX? Thanks in advance for any comments.
Well I don't know what Baud speeds you're going to be needing, but you can turn any pin into RX and TX pins in software, but you're limited to 9600 BPS and I'm sure there are a few other disadvantages.
Take a look at the SoftwareSerial tutorial and Reference pages:
Using this will free up your TX and RX pins. I don't believe you can still debug using Serial when you have TX and RX hooked up. After uploading a sketch, and if you have nothing connected to your TX pin, then you're able to send information back, but once you connect something to it you should have some problems.
But, as far as debugging goes when they're connected.. You may be able to use a LCD to debug (depending on how much information needs to be debugged, obviously) And.. well, maybe somebody else can offer some more advanced techniques, but this is as far as I've gotten myself!