12 years ago.

Non blocking getc (apparently...)

Hi I've put together a program that delivers live flowrate and graviational angle (from a pulsing flowmeter and a triple axis analog accelerometer) to terminal. However I now need to adjust the offsets so as to calibrate this display, from a keyboard. I copied the pc.getc from the servo control example, but this only gives an output when a key is pressed, rather than a live display I can then adjust with the right keys. Any idea how I can do what I need? Best Robin

1. include "counter.h"
2. include "mbed.h"

Serial pc(USBTX, USBRX); counter SF800 (p29); Timer t_a, t_b; AnalogIn z(p20); AnalogIn y(p19); AnalogIn x(p18);

int main() {

t_a.start(); t_b.start(); int a_init_pulses = 0; int b_init_pulses = 0; float flowconvert = 2500; float flowrate = 0; float inclin = 0; float inc_offset = 0; int time_window = 1000;

bool a_b_flip_flop = true; if true use window a

pc.printf("\n\r***\n\rMBED restarted\n\r***\n");

while (1) { wait(0.25);

pc.printf("Before switch\n");

switch(pc.getc()) { case '7': flowconvert += 1; break; case '1': flowconvert -= 1; break; case '9': inc_offset += 1; break; case '3': inc_offset -= 1; break; }

pc.printf("After switch\n");

if (a_b_flip_flop) { flowrate = (float)(SF800.getPulses() - a_init_pulses)/(flowconvert * t_a.read_ms() / 60000); } else { flowrate = (float)(SF800.getPulses() - b_init_pulses)/(flowconvert * t_b.read_ms() / 60000); }

if (t_a.read_ms() > time_window) { switch to window B

pc.printf("\rswitching to window B = %i pulses detected in window A\n", SF800.getPulses() - a_init_pulses);

t_a.reset(); a_b_flip_flop = false; a_init_pulses = SF800.getPulses(); }

if (t_a.read_ms() > time_window/2 && !a_b_flip_flop) { switch to window A

pc.printf("\rswitching to window A = %i pulses detected in window B\n", SF800.getPulses() - b_init_pulses);

t_b.reset(); a_b_flip_flop = true; b_init_pulses = SF800.getPulses(); }

inclin = (atan2(y.read(), z.read()) * 180.0 / 3.141592654) + inc_offset;

pc.printf("\rflowrate = %.3f ml/min", flowrate); pc.printf(" Inclination G %.1f degrees", inclin); } }