Design PISO register for custom UART Transmitter

Question

Problem: Design PISO register for custom UART Transmitter. Solve this hands-on electronics task on EWskills.

Accepted Answer

UART Parallel-to-Serial Conversion: UART converts parallel data into a serial bit stream, enabling transmission over a single data line.

Dual-Mode Control: The CTR input controls 2-to-1 multiplexers, selecting between parallel loading (CTR = 0) and serial shifting (CTR = 1).

LSB-First Transmission: D0 loads into Q0 and is transmitted first, while D1–D3 shift through Q3 → Q2 → Q1 → Q0.

1 Hz Clock Synchronization: A 1 Hz clock ensures uniform bit intervals for reliable data transmission.

Register Flushing: During shifting, zeros enter through Q3, clearing the register after the 4-bit transmission completes.

77. Design PISO register for custom UART Transmitter