ENGR 433 -  Lab X 2024 Spring

Name: Ian Van Horn
Email: imvanhorn1@gmail.com
 HW 7

This homework introduces UART communication

This lab requires vivado, arduino IDE, and Tera Terminal



Task 1: Counter with Debounce. (25 points).
*This task was used as a quiz, the code in mostly re-used form the quiz


Figure 1-1: Counter code

The debounce module stops the button from showing many fast (bounce) signals for each press. If the appropriate count has passed and the button is pressed, digit is incrimented and a case statment is used to assign the correct segments on the ssd to the correct value.


Video 1-1: Demonstration of counter

Task 1: UART transmitter(25 points).

Figure 2-1: Code for UART transmitter

A UART package carries 11 bits. 8 data bits, a stop,start, and a parity bit. When idle the transmitter is at 1. To start a package transmittion the signal is pulled low. The 9 bits of information are transmitted, then the signal is pulled high again.
The baud rate is the rate that information is transmitted. txData holds a sandwhich of "data" and the high and low start/end signal. No parity bit is used. The LOAD_BIT state loads each bit of the tx data into the txBit, which is assigned to uart_tx.


Figure 2-2: Serial moniter output

Task 3: UART reciever(25 points).

Figure 3-1: Code for UART reciever

If the rx signal is pulled low, signaling the start of transmission, RDY passes the state to START. Timer is incrimented until half of the baud rate in START so the timer counts to baud_timer in the middle of the next bit. At the appropriate time the state is passed to WAIT. When reading data, SIPO register is used, rx is assigned to an address in rxdata. Then an xor statment is used to check the parity bit.


Figure 3-2: Demo of UART reciever




Task 4: UART reciever with SSD (25 points).

Figure 4-1: Code to add SSD to UART reciever

In the testbench, the wire "out" holds the value of the recieved char. A switch statment is made to display the correct digit on the SSD based on the recieved ASCII code. When the recieved code was not for a digit, E was displayed. IMPORTANT: The parity generator from Tera Terminal did not work for some reason, when set to even, any charcter with an even number of 1's threw a parity error. When set to odd, the same happened with numbers with an odd number of 1's. When disabled the code worked as expected




Video 4-1: Demo of SSD



Conclusion: The Tera Terminal caused some confusion, but overall the UART implimentation went smoothly.