Calculadora de Temporización Modbus RTU
Calcula el tiempo de carácter, intervalo entre tramas (3.5T) y tiempo de trama para Modbus RTU.
Fórmula
T_{char} = \frac{1+8+P+S}{baud\_rate},\quad T_{3.5} = 3.5 \times T_{char}
Referencia: Modbus Application Protocol V1.1b3, Modbus.org
Cómo Funciona
Modbus RTU is a serial communication protocol that uses a master-slave architecture for industrial control systems. The protocol defines precise timing requirements for frame transmission, which are critical for reliable communication. Timing calculations involve determining character transmission duration, inter-frame spacing, and total frame time based on baud rate and data configuration.
Ejemplo Resuelto
Problem: Calculate character time and inter-frame gap for a Modbus RTU transmission at 9600 baud with 8 data bits, no parity, and 1 stop bit Solution: 1. Total bits per character = 1 (start) + 8 (data) + 0 (parity) + 1 (stop) = 10 bits 2. Character time = 10 bits / 9600 bps = 1.04 ms 3. Inter-frame gap = 3.5 * 1.04 ms = 3.65 ms 4. For a frame with 4 data bytes, total frame time = (4+4) * 1.04 ms = 8.32 ms
Consejos Prácticos
- ✓Always verify device-specific Modbus RTU timing tolerances
- ✓Use oscilloscope to confirm actual transmission timing
- ✓Consider temperature and environmental factors affecting timing
- ✓Test communication at multiple baud rates for robustness
Errores Comunes
- ✗Miscalculating total bits per character
- ✗Ignoring inter-frame spacing requirements
- ✗Not accounting for parity and stop bits
- ✗Assuming constant timing across different baud rates
Preguntas Frecuentes
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