File content as of revision 2:e7ce63ada1d2:

#include "mbed.h"
#include "rtos.h"
#include "FastAnalogIn.h"
#include "PID.h"

PID I(10.0, 0.01, 0.0, 0.01);

AnalogOut Iset(PTE30);
FastAnalogIn Iget(PTE20);
AnalogIn Vbat(PTB0);
bool active = true;
float k = 0.01, iget = Iget.read(), vbat = Vbat.read(), vbat_rest = Vbat.read();
void filter() {
    if (active) {
        iget = k * Iget.read() * 32.9697 + 0.0001666 + (1 - k) * iget;
        vbat = k * Vbat.read() * 36.7538 + (1 - k) * vbat;
    }
    if (Iset.read() == 0)
        vbat_rest = k * Vbat.read() * 36.7538 + (1 - k) * vbat_rest;
}
void rest(const void *) {
    while (true) {
        Thread::wait(5000);
        if (Iset.read() > 0) {
            active = false;
            Iset.write_u16(16);
            Thread::wait(400);
            Iset.write_u16(0);
            Thread::wait(100);
            active = true;
        }
    }
}
int flop = 0;
void adjust() {
    //flop = (flop + 1) % 4;
    //Iset.write(flop == 0? 0.2/4.61 : 0);
    if (active) {
        I.setProcessValue(iget);
        Iset = I.compute();
    }
}

Serial pc(USBTX, USBRX);
void ui(const void*) {
    while (true) {
        Thread::wait(100);
        while (pc.readable()) {
            pc.getc();
            I = I + 0.1;
        }
    }
}

int main()
{
    pc.baud(115200);

    I.setInputLimits(0, 100);
    I.setOutputLimits(0, 1);
    I = 0;
    I.setMode(AUTO_MODE);

    Ticker t2;
    t2.attach_us(&filter, 1000);
    Ticker t;
    t.attach(&adjust, I.getInterval());
    Thread t3(&rest);
    Thread t4(&ui);

    while (true) {
        //pc.printf("Iset %f    Iget %6d %f    Vbat %6d %f    \r", Iset.read(), Iget.read_u16(), Iget.read(), Vbat.read_u16(), Vbat.read());
        pc.printf("Iset %f      Iget %8d %f %f", Iset.read(), Iget.read_u16(), Iget.read() * 32.9697 + 0.0001666, iget);
        pc.printf("      Vbat %8d %f %f %f\r", Vbat.read_u16(), Vbat.read() * 36.7538, vbat, vbat_rest);
        Thread::wait(500);
    }
}