50 lines
1.1 KiB
Arduino
50 lines
1.1 KiB
Arduino
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// Basic demo for configuring the MCP4728 4-Channel 12-bit I2C DAC
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#include <Adafruit_MCP4728.h>
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#include <Wire.h>
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Adafruit_MCP4728 mcp;
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int bpm = 98;
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float beat_s = 60.0 / (float)bpm;
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int beat_m = round(1000.0 * beat_s);
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long init_t;
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float pi = 3.141592653589793;
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float mod_a = pi;
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float mod_b = pi / 4.0;
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float mod_c = pi / 3.0;
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float mod_d = pi / 5.0;
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void setup(void) {
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Serial.begin(115200);
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while (!Serial)
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delay(10); // will pause Zero, Leonardo, etc until serial console opens
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if (!mcp.begin(0x64)) {
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Serial.println("Failed to find MCP4728 chip");
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while (1) {
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delay(10);
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}
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Serial.println("MCP4728 initialised");
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}
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init_t = millis();
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mcp.setChannelValue(MCP4728_CHANNEL_B, 0);
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}
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void loop() {
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long now = millis();
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long mod_t = (now - init_t);
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float tf = (float)mod_t / (float)beat_m;
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uint16_t a = round(4095.0 * (0.5 + 0.5 * sin(mod_a * tf)));
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uint16_t b = round(4095.0 * (0.5 + 0.5 * sin(mod_b * tf)));
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uint16_t c = round(4095.0 * (0.5 + 0.5 * sin(mod_c * tf)));
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uint16_t d = round(4095.0 * (0.5 + 0.5 * sin(mod_d * tf)));
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mcp.fastWrite(a, b, c, d);
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}
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