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refactor(rmt): refactored RMT loopback example #11221

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Merged
merged 2 commits into from
Apr 9, 2025
Merged

refactor(rmt): refactored RMT loopback example #11221

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1e6ff84
feat(rmt): refactored RMT loopback example
SuGlider Apr 6, 2025
940ecfb
ci(pre-commit): Apply automatic fixes
pre-commit-ci-lite[bot] Apr 9, 2025
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51 changes: 33 additions & 18 deletions libraries/ESP32/examples/RMT/RMTLoopback/RMTLoopback.ino
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Original file line number Diff line number Diff line change
@@ -1,4 +1,4 @@
// Copyright 2023 Espressif Systems (Shanghai) PTE LTD
// Copyright 2025 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
Expand Down Expand Up @@ -35,40 +35,55 @@
rmt_data_t my_data[256];
rmt_data_t data[256];

static EventGroupHandle_t events;

#define RMT_FREQ 10000000 // tick time is 100ns
#define RMT_NUM_EXCHANGED_DATA 30
#define RMT_NUM_EXCHANGED_DATA 32

void setup() {
Serial.begin(115200);
events = xEventGroupCreate();

if (!rmtInit(RMT_TX_PIN, RMT_TX_MODE, RMT_MEM_NUM_BLOCKS_1, RMT_FREQ)) {
Serial.println("init sender failed\n");
}
if (!rmtInit(RMT_RX_PIN, RMT_RX_MODE, RMT_MEM_RX, RMT_FREQ)) {
Serial.println("init receiver failed\n");
}
Serial.println();
Serial.println("RMT tick set to: 100ns");

// End of transmission shall be detected when line is idle for 2us = 20*100ns
rmtSetRxMaxThreshold(RMT_RX_PIN, 20);
// Disable Glitch filter
rmtSetRxMinThreshold(RMT_RX_PIN, 0);

Serial.println("real tick set to: 100ns");
Serial.printf("\nPlease connect GPIO %d to GPIO %d, now.\n", RMT_TX_PIN, RMT_RX_PIN);
}

void loop() {
// Init data
int i;
for (i = 0; i < 255; i++) {
data[i].val = 0x80010001 + ((i % 13) << 16) + 13 - (i % 13);
// create multiple pulses with different width to be sent
for (int i = 0; i < 255; i++) {
data[i].level0 = 1; // HIGH
data[i].duration0 = 1 + 13 - (i % 13); // number of Tick on High
data[i].level1 = 0; // LOW
data[i].duration1 = 1 + (i % 13); // number of Ticks on Low
my_data[i].val = 0;
}
data[255].val = 0;
Serial.println();
Serial.println("====================================================================================================");
Serial.println("Preloaded Data that will sent (time in 0.1us):");
// Printout the received data plus the original values
for (int i = 0; i < RMT_NUM_EXCHANGED_DATA; i++) {
Serial.printf("%08lx=[%c 0x%02x|%c 0x%02x] ", data[i].val,
data[i].level0 ? 'H' : 'L', data[i].duration0,
data[i].level1 ? 'H' : 'L', data[i].duration1);

if (!((i + 1) % 4)) {
Serial.println();
}
}
Serial.println("====================================================================================================");
Serial.printf("Please connect GPIO %d to GPIO %d, now.", RMT_TX_PIN, RMT_RX_PIN);
Serial.println();
Serial.println();
}

void loop() {
// Start an async data read
size_t rx_num_symbols = RMT_NUM_EXCHANGED_DATA;
rmtReadAsync(RMT_RX_PIN, my_data, &rx_num_symbols);
Expand All @@ -84,13 +99,13 @@ void loop() {
Serial.printf("Got %d RMT symbols\n", rx_num_symbols);

// Printout the received data plus the original values
for (i = 0; i < 60; i++) {
for (int i = 0; i < RMT_NUM_EXCHANGED_DATA; i++) {
Serial.printf("%08lx=%08lx ", my_data[i].val, data[i].val);
if (!((i + 1) % 4)) {
Serial.println("");
Serial.println();
}
}
Serial.println("\n");
Serial.println();

delay(500);
delay(2000);
}
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