PN522 reader as keyboard using Cjmcu Beetle (ATMEGA32U4)

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Human: I'm using a PN522 reader that sends data as keyboard input to my PC via an Arduino CJMCU Beetle (ATMEGA32U4). The Beetle is programmed like a Leonardo using the Arduino IDE 1.8.5, and the PN522 is set up for I2C communication using a dip switch on the module (1=on, 2=off). When ready, a yellow LED with resistor lights up; an active buzzer beeps when the card is good, and double beeps when the card is wrong (with the LED blinking). I can read a maximum of 16 characters from the card in block 5. To make it work with my Italian keyboard, I had to add < and > characters, which are very hard to send. The keyboard.h library is for English keyboard scancode only. Libraries used: Adafruit_PN532.h and Keyboard.h for Leonardo. Code (missing hashtag character): #include <Keyboard.h> // Keyboard.h #include <Wire.h> // Wire.h #include <Adafruit_PN532.h> // Adafruit_PN532.h #define PN532_IRQ A0 #define PN532_RESET 15 #define PIN_TONE 11 #define PIN_LED 10 #define PLAY_ERROR tone(11, 100,500) #define PLAY_OKAY1 tone(11, 600, 200) #define PLAY_OKAY2 tone(11, 700, 200) uint8_t success; // Flag to check if there was an error with the PN532 uint8_t uid[] = { 0, 0, 0, 0, 0, 0, 0 }; // Buffer to store the returned UID uint8_t uidLength; // Length of the UID (4 or 7 bytes depending on ISO14443A card type) uint8_t currentblock; // Counter to keep track of which block we're on bool authenticated = false; // Flag to indicate if the sector is authenticated uint8_t data[16]; // Array to store block data during reads uint8_t keyuniversal[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF }; // Keyb on NDEF and Mifare Classic should be the same Adafruit_PN532 nfc(PN532_IRQ, PN532_RESET); void setup(void) { delay(1000); pinMode(PIN_LED, OUTPUT); nfc.begin(); uint32_t versiondata = nfc.getFirmwareVersion(); if (!versiondata) { PLAY_ERROR; PLAY_ERROR; while (1) { digitalWrite(PIN_LED, HIGH); delay(300); digitalWrite(PIN_LED, LOW); }; // halt } nfc.SAMConfig(); // configure board to read RFID tags digitalWrite(PIN_LED, HIGH); Keyboard.begin(); } void loop(void) { // Wait a bit before trying again digitalWrite(PIN_LED, LOW); delay(2000); digitalWrite(PIN_LED, HIGH); success = nfc.readPassiveTargetID(PN532_IRQ, uid, uidLength); if (!success) { PLAY_ERROR; return; } authenticated = true; // Authenticated ... we should be able to read the block now success = nfc.mifareclassic_ReadDataBlock(currentblock, data); if (!success) { PLAY_ERROR; return; } // Read successful for(int i=0;data[i]>0;i++) { if(data[i]=='<') { Keyboard.write(236); // < } else if(data[i]=='>') { Keyboard.press(KEY_LEFT_SHIFT); Keyboard.write(236); // > Keyboard.release(KEY_LEFT_SHIFT); } else { Keyboard.print((char)data[i]); } } PLAY_OKAY1; delay(100); PLAY_OKAY2; PCB Wires: Yellow to led Blue GND for led and buzzer Green to buzzer PN522: Black GND Red VCC White to SDA Gray to SCL Purple to IRQ Pink to RTS0