UART (Universal Asynchronous Receiver-Transmitter) is a serial communication protocol used for asynchronous data transfer between devices. It does not require a separate clock signal; instead, it uses a baud rate to synchronize communication.
UART loopback is a special mode where the transmitted (TX) data is directly routed to the receiver (RX), allowing self-testing without external connections.
Debugging UART Transmission → Ensures data is sent and received correctly.
No External Hardware Required → TX is internally connected to RX.
Self-Testing → Helps verify UART functionality in an FPGA or microcontroller.
- This block is responsible for sending serial data.
- It converts parallel 8-bit data into a serial bitstream.
- Generates Start Bit (
0), Data Bits (LSB First), and Stop Bit (1).
- Instead of sending data to an external device, TX (
uarttx) is directly connected to RX (uartrx). - Implements a hardware loopback, allowing data sent from TX to be immediately received by RX.
- Reads the serial data from TX via the direct connection.
- Reconstructs the original 8-bit parallel data.
- This allows testing UART transmission without an external receiver.
assign uarttx = uartrx;- Any data sent on uarttx is instantly received on uartrx.
- This eliminates the need for external connections during testing.
- Helps debug UART transmission in an FPGA-based system.