mirror of
https://github.com/UtilitechAS/amsreader-firmware.git
synced 2026-01-15 16:25:43 +00:00
37 lines
629 B
C++
37 lines
629 B
C++
#include <SoftwareSerial.h>
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#define RX_PIN 10
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#define TX_PIN 11
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SoftwareSerial mySerial(RX_PIN, TX_PIN);
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// https://en.wikipedia.org/wiki/Binary_Gray_sequence
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static unsigned int binary_to_gray(unsigned int num)
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{
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return num ^ (num >> 1);
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}
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void setup() {
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mySerial.begin(9600);
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}
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void loop() {
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static unsigned int i = 0;
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static unsigned int ch = 0;
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// Change the character more seldom than each loop entry.
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if (i++ > 20) {
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i = 0;
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// 127 => leave the last bit sent always zero.
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if (++ch > 127) {
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ch = 0;
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}
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}
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mySerial.write(binary_to_gray(ch));
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// 9600 bps => 8 bit = 8/9600s ~ 0.8ms
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delay(50);
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}
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