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var i2c, ina, wa, epoch = new Date();
var INA226 = require("INA226");
INA226.prototype.r3 = function() {
return {
u: this.rd(0x02) * 0.00125,
p: this.rd(0x03) * 25000 * this.currentLSB,
i: this.rds(0x04) * 1000 * this.currentLSB,
o: (this.rd(0x06) & 4) !== 0
};
};
function r3Print() {
var i = ina.r3(); print(`${i.i.toFixed(4)} mA, ${i.u.toFixed(4)} V`);
}
/**
* Data format:
* 'x' literal 1 byte
* timestamp in Uint32 4 byte
* measured values in float32: Voltage, Current, Power
* 3*4 byte
* overflow bool 1 byte
* 'y\n' literal 2 byte
* Data length: (4 + 3*4 + 1) = 17 byte
* "packet" length: 1 + (4 + 3*4 + 1) + 2 = 20 byte
*/
function r3Send() {
var i = ina.r3(); Bluetooth.write('x', new Int32Array([Math.round(new Date() - epoch)]).buffer, new Float32Array([i.u, i.i, i.p]).buffer, i.o, 'y\n');
}
function startSend() {
stop();
wa = setWatch(r3Send, D4, {edge: "falling", repeat: true});
ina.r3();
}
function stop() {if (wa) {wa = clearWatch(wa);} }
function onInit() {
i2c = I2C1;
i2c.setup({sda: D11, scl: D5, bitrate: 400000});
pinMode(D4, "input_pullup");
ina = new INA226(i2c, {
average: 16,
// default conversion time: 1.1ms * 2 (Vbus & Shunt) => 454,5455 measurement / sec
// 128,256,512 or 1024
// avg 64: 7.18 sample/sec, 142.86ms/sample => 140 byte / sec
// avg 16: 28 sample/sec, 35.71ms/sample => 560 byte / sec
// avg 4: 112 sample/sec, 8.93ms/sample => 2240 byte / sec ==> maybe too much...
// avg 1: 448 sample/sec ==> definitely too much, fastest connection interval is 7.5ms
// INA 226 conversion time: 140us, 204us, 332us, 588us, 1100us (default)
shunt: 1,
maxCurrent: 0.082
});
NRF.on('disconnect', function() {stop(); digitalPulse(LED1, 1, 200);});
NRF.on('connect', function() {digitalPulse(LED2, 1, 200);});
}
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