i use the following method to check my serial connection
1. short the tx and rx pins of the cable and check whether the data is echoded back
2.remove the max 232 and short the pins tx and rx in it and find whether the data is echoed back
these two methods tests the cable and the tracks upto the max232 are working well
now put the max232 and remove the micro controller and short the tx and rx pins in the micro controllers base .now power on the circuit and test whether the data is echoed back
this checks the max232 working and also the connection till the micro controller
if all the above tests are working well then there is greater probability that the problem is in the micro controller or the program written into it.

use some other serial communication utility like brays terminal with hardware handshanking none

regards
pradheep