尝试使用集成的 OLED 和附加的 SD 卡对 Heltec ESP32 LoRa 进行编码。
我已经让 SD 卡 (CS 21) 和 LoRa (CS 18) 单独工作，但是当我尝试让两者在同一个程序中工作时，我做不到。
//
// Heltec 32 LoRa OLED (with SD Card)
// ______________
// Gnd | | USB| | Gnd
// 5v | | port| | 5v
// 3v3 | |_____| | 3v3
// Gnd | ALL | 36<- <- : Input Only!
// Rx | GPIO | 37<-
// Tx | 3.3v | 38<-
// RST | ________ | 39<-
// 0 | | | | 34<-
// (SCL) 22 | | | | 35<-
// SPI MISO 19 | | | | 32<-
// 23 | | | | 33<-
//LoRa CS(HI)18 | | | | 25 (LED)
// SPI SCK 5 | | OLED | | 26 LoRa IRQ
//OLED SCL 15 | | | | 27 SPI MOSI
// 2 | | | | 14 LoRa Rst
//OLED SCA 4 | | | | 12
// 17 | |________| | 13
//OLED RST 16 |______________| 21 (SD_CS)
//
#include <mySD.h> // SD Card (VMA304)
#include "SSD1306.h" // OLED
#include <LoRa.h> // LoRa
File root;
// OLED Pin
#define SDA 4 // Serial Data
#define SCL 15 // Serial Clock
#define oRST 16 // Reset
#define OLED_ADDR 0x3C // OLED display TWI address
SSD1306 display(OLED_ADDR, SDA, SCL);
// OLED screen text rows:
#define row1 0 // y=0 is top row of size 1 text
#define row2 10
#define row3 20
#define row4 30
#define row5 40
#define row6 50 // row7 at 70 is too low
// SPI port #2: SD Card Adapter
#define SD_CLK 5
#define SD_MISO 19
#define SD_MOSI 27
#define SD_CS 21
// SPI port: LoRa (SX1278)
// LoRa Pin
#define LoRa_SCK 5
#define LoRa_MISO 19
#define LoRa_MOSI 27
#define LoRa_CS 18
#define LoRa_RST 14 // LoRa_Reset
#define DI0 26 // LoRa_IRQ
#define BAND 915E6 // other freq: 433E6 // or ? LoRa f(MHz)
#define Select LOW // Low CS means that SPI device Selected
#define DeSelect HIGH // High CS means that SPI device Deselected
File sessionFile; // SD card filenames are restricted to 8 characters + extension
int counter = 0; // count sent LoRa messages
/***********************************************************/
void setup(){
// set output pins
pinMode(oRST,OUTPUT);
pinMode(SD_CS,OUTPUT);
pinMode(LoRa_CS,OUTPUT);
digitalWrite(LoRa_CS, DeSelect);
// set GPIO16 Low then High to Reset OLED
digitalWrite(oRST, LOW);
delay(50);
digitalWrite(oRST, HIGH);
Serial.begin(115200);
while(!Serial); // wait to connect to computer
display.init();
display.flipScreenVertically();
display.setFont(ArialMT_Plain_10);
display.setTextAlignment(TEXT_ALIGN_LEFT);
display.clear();
display.display();
Serial.print("Initializing SD card...");
digitalWrite(SD_CS, Select); // SELECT (Low) SD Card SPI
if (!SD.begin( SD_CS, SD_MOSI, SD_MISO, SD_CLK )) {
Serial.println("initialization failed!");
// now what?
} else {
Serial.println("initialization done.");
display.drawString( 5,row1,"SD Card OK!" );
display.display();
delay(1000);
}
/* open "test.txt" for writing */
root = SD.open("test.txt", FILE_WRITE);
if (root) {
root.println("Hello world!");
root.flush();
root.close();
} else { // file open error
Serial.println("error opening test.txt");
}
display.drawString( 5,row2,"Wrote in test.txt" );
display.display();
delay(100);
/* after writing, then reopen the file and read it */
root = SD.open("test.txt");
if (root) { /* read from the file to the end of it */
while (root.available()) { // read the file
Serial.write(root.read());
}
root.close();
} else {
Serial.println("error opening test.txt");
}
display.drawString( 5,row3,"Read from test.txt" );
display.display();
delay(100);
// done testing the SD Card
digitalWrite(SD_CS, DeSelect); // DESELECT (high) SD Card SPI
SD.end();
delay( 100 );
// now test the LoRa
SPI.begin( LoRa_SCK, LoRa_MISO, LoRa_MOSI, LoRa_CS );
LoRa.setPins( LoRa_CS, LoRa_RST, DI0 );
digitalWrite(LoRa_CS, Select); // SELECT (low) LoRa SPI
Serial.println("LoRa Sender");
if (!LoRa.begin(BAND)) {
Serial.println("Starting LoRa failed!");
display.drawString( 5, row4, "LoRa Init Failed!");
display.display();
// now what?
} else {
Serial.println("LoRa Initial OK!");
display.drawString( 5, row4, "LoRa Initialized OK!");
display.display();
delay(1000);
}
Serial.println("Setup done!");
}
void loop() {
Serial.print("Sending packet: ");
Serial.println(counter);
display.clear();
display.setFont(ArialMT_Plain_16);
display.drawString(3, 5, "Sending packet ");
display.drawString(50, 30, String(counter));
display.display();
// send packets
LoRa.beginPacket();
LoRa.print("Hi. Sent packet #");
LoRa.print(counter);
LoRa.endPacket();
counter++;
delay(500);
}
我有一个 LoRa 接收器来读取消息。使用上面发布的代码，SD 卡就可以工作了。LoRa 说它正在传输消息，但接收者看不到它们，并且在 4 条消息后停止。