The 2nd one could be either a or b. I'd guess b.

http://msdn.microsoft.com/en-us/library/system.io.ports.serialport(VS.80).aspx

[EDIT]

Try using a MaskedText box with a regular expression mask to format the text in a cleaner fashion.

The disadvantages of using a circuit instead of a micro are easy to say. Development time increases (especially if it dont work right the first time). Complexity of the circuit board increases. Cost increases. Flexibility decreases to practically 0. Im sure your professor will point these out to you.

About the only advantages would be if the circuit is going to do high speed calculations or conversions. Using a dedicated circuit would free up processing time from the micro that would be better spent on other tasks. If you are planning on doing this, I would recommend using an FPGA for the logic. This would allow the design to be flexible, and decrease design time because you dont have to make a new circuit board if the first try doesnt work. Cost is low due to only having one IC (plus an EEPROM for the config data). I think this is your only way of convincing your prof. that a dedicated circuit would be better. Even then, it depends on what other functions the design must also do.

To the other person: The 8 bit micro is one of the most widely use micro's for embedded applications. The price vs performance is unbeatable. Today's 8 bit micro's have tha ability of supporting larger RAM and ROM (using paging) than just 64K. They also have more than 1 serial port. Most have at least 2, plus USB, I2C, SPI. Better ones have the ability to do ethernet also. Some have the ability of 50 MIPS or more. Not bad for a micro that costs less than $20 bucks.