A Reconfigurable Peripheral Interface Controller-Based Test Platform: Co-Design, Analytical Characterization, and Low-Cost Hardware Implementation

Abstract

Practical training on embedded systems is a very good way to assess the skills of students in firmware development, real-time programming and hardware–software co-design. However, many low- and middle-income institutions still use closed, proprietary boards, such as the Altera DE series, which hide the physical behavior. To address this, a low-cost, fully reconfigurable Microcontroller Test Board (MTB) was designed and technically validated for application in undergraduate laboratories. The MTB is manufactured as a one-sided through-hole PCB via toner transfer and FeCl3 etching, with a PIC18F2550 in-circuit programmer and support for 28- and 40-pin targets including the PIC16F877A. The MTB integrates six functional blocks, providing five canonical input/output modalities on a single regulated 5 V/0.56 A rail: (1) an ICSP programmer; (2) a multiplexed seven-segment display; (3) an 8 × 8 LED matrix; (4) a matrix keypad with LCD calculator; and (5) a 10-bit ADC stage. All subsystems operate with a flicker-free refresh rate > 122 Hz. The total board power consumption is 6.72 W at 12 V DC, with the linear regulator dissipating 3.92 W under full load. Probe points allow for signal transparency. Models for regulator dissipation, ADC quantization, multiplex refresh duty cycle, LED current limiting, oscillator timing, matrix-scanning latency, LCD timing, keypad response and Fe3+ with Cu etch kinetics were first-principles. Bench measurements agree with model predictions to less than 3% error, and confirm worst-case design margins. The MTB provides analytical rigor with accessible hardware to enable measurable experiments in microcontroller labs. The platform is cost-effective, with a material cost of less than USD 18. Each signal is routed to probe points, providing significant cost reduction from commercial trainers, and a transparent hands-on laboratory resource for engineering curricula with limited resources.