ATmega32U4 nintendospy.ino

const uint8_t gamecube_pin = PD0;
const uint8_t gamecube_prefix = 25;
const uint8_t gamecube_bitcount = 64;
unsigned char data[gamecube_bitcount + gamecube_prefix];

#define PIN_READ(pin)  (PIND & (1 << pin))
#define TWOMICROSECOND_NOPS "nop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\nnop\n"
#define WAIT_FALLING_EDGE(pin) while(!PIN_READ(pin)); while(PIN_READ(pin));

void setup()
{
  // Activate gamecube pin as an input
  DDRD &= ~(1 << gamecube_pin);
    
  Serial.begin(115200);
}

void loop()
{
  uint8_t bits_left = gamecube_prefix + gamecube_bitcount;
  unsigned char* ptr = data;

  noInterrupts();

  // Collect data
  while (true) {

    // Wait for the data line to go low
    WAIT_FALLING_EDGE(gamecube_pin);

    // Wait 2us between line reads
    asm volatile(TWOMICROSECOND_NOPS);

    // Read a bit and store in the header
    *ptr = PIN_READ(gamecube_pin);
    ++ptr;

    if (--bits_left == 0) {
      break;
    }
  }

  interrupts();

  Serial.write(data + gamecube_prefix, gamecube_bitcount);
  Serial.write('\n');
}

Stumbled upon this code looking for ways to miniaturize a setup. Were you able to get this working on a 32u4? looking particularly at the beetle

Ah man, this has been a while. The point of this project wasn't for control. I used it to just read commands off the wire and interpret them with nintendospy. I ended up using a 328p and modified this for two controllers and it worked fine.

Yeah, that's what I was hoping to do with the smaller chip. Been doing it with the 328p just fine, and got greedy for something smaller :) Thanks

…

On Thu, Jan 16, 2020 at 10:46 AM Justin Bruce Van Horne < ***@***.***> wrote: Ah man, this has been a while. The point of this project wasn't for control. I used it to just read commands off the wire and interpret them with nintendospy. I ended up using a 328p and modified this for two controllers and it worked fine. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <https://gist.github.com/08c2e4c768d6dddc69d8?email_source=notifications&email_token=ABT6INSHNA5NTXYBUTJAI6DQ6CFNBA5CNFSM4KHW4AW2YY3PNVWWK3TUL52HS4DFVNDWS43UINXW23LFNZ2KUY3PNVWWK3TUL5UWJTQAF7V3A#gistcomment-3140528>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABT6INVNLF7WSKFZRGNXN7LQ6CFNBANCNFSM4KHW4AWQ> .