i am trying to learn the implementation of the Max232 chips. I understand their function of converting 5v / 3v logic levels to +/-12V RS232.
Okay but how does one implement this? Adding it to lets say a 328s Rx Tx would be point less because they already talk to serial just fine.
Perhaps my understanding of what this does is misconstrued , i seem to believe it would be like adding an additional rx tx to a uC?
if so then if , just for example , i had a board with 2 usb connectors one wired to the 328s rx/tx and another to the max232 i would get 2 different com ports?
that might be totally wrong , hence the post.
I kind of want to ask other question but they are based on my belief so ill wait..
The ATmega328 can talk to the USB-to-TTL_Serial converter because they both use TTL (5v) serial signals.
The ATmega328 cannot talk directly to an RS232 serial port (such as the 9-pin D connector serial port of an old PC) because the +/- 12v RS232 signals would damage the 5V TTL input of the ATmega. That is where you would use a MAX232 level shifter.
OH! so it is just to shift the Atmega's rt/tx level up to RS232, i was thinking it was like adding a separate independent serial connection, so in essence you would have rx1 and rx2 to be used independent of each other. oh well....that would of been great though
I think what you may be thinking is adding a part like a SPI to UART adapter for more serial ports:
Other versions available also. Maxim even has a quad serial port part.
Skyjumper has experience using a Dual serial part, I can look up the part number when I get home.
now that is what the doctor ordered! thanks CR i will study this datasheet now.
Or you can move up to part like the '1284 that has 2 serial ports already, and additional I/O lines as well, and still in a friendly DIP package.
that is the one you have pictured there on the bobuino right?
how does one address the second serial in the ide?
Serial,Serial1
i cannot grasp my head around the complexity.. ha..like always thanks for the point in the right direction. research time.
Wanna guess how the Mega2560 does 4 ports? 
haha ill cross that bridge when i get to it