lan8720 phy test arduino.ino

uint8_t txpin1 = 4;
uint8_t txpin2 = 5;
uint8_t txpen = 6;
uint8_t powerpin = A3;
uint32_t counter = 0;

uint8_t phy_address = 1; // apparently hardcoded on board

uint8_t smi_clock = 8;
uint8_t smi_data = 9;

#define CLK_DELAY_MICROS 1


//LAN8720 PHY registers
#define LAN8720_BMCR                      0x00
#define LAN8720_BMSR                      0x01
#define LAN8720_PHYID1                    0x02
#define LAN8720_PHYID2                    0x03
#define set                      0x04
#define LAN8720_ANLPAR                    0x05
#define LAN8720_ANER                      0x06
#define LAN8720_MCSR                      0x11
#define LAN8720_SMR                       0x12
#define LAN8720_SECR                      0x1A
#define LAN8720_SCSIR                     0x1B
#define LAN8720_ISR                       0x1D
#define LAN8720_IMR                       0x1E
#define LAN8720_PSCSR                     0x1F

//Basic Control register
#define LAN8720_BMCR_RESET                0x8000
#define LAN8720_BMCR_LOOPBACK             0x4000
#define LAN8720_BMCR_SPEED_SEL            0x2000
#define LAN8720_BMCR_AN_EN                0x1000
#define LAN8720_BMCR_POWER_DOWN           0x0800
#define LAN8720_BMCR_ISOLATE              0x0400
#define LAN8720_BMCR_RESTART_AN           0x0200
#define LAN8720_BMCR_DUPLEX_MODE          0x0100

//Basic Status register
#define LAN8720_BMSR_100BT4               0x8000
#define LAN8720_BMSR_100BTX_FD            0x4000
#define LAN8720_BMSR_100BTX_HD            0x2000
#define LAN8720_BMSR_10BT_FD              0x1000
#define LAN8720_BMSR_10BT_HD              0x0800
#define LAN8720_BMSR_100BT2_FD            0x0400
#define LAN8720_BMSR_100BT2_HD            0x0200
#define LAN8720_BMSR_EXTENDED_STATUS      0x0100
#define LAN8720_BMSR_AN_COMPLETE          0x0020
#define LAN8720_BMSR_REMOTE_FAULT         0x0010
#define LAN8720_BMSR_AN_CAPABLE           0x0008
#define LAN8720_BMSR_LINK_STATUS          0x0004
#define LAN8720_BMSR_JABBER_DETECT        0x0002
#define LAN8720_BMSR_EXTENDED_CAPABLE     0x0001

//PHY Identifier 1 register
#define LAN8720_PHYID1_PHY_ID_MSB         0xFFFF
#define LAN8720_PHYID1_PHY_ID_MSB_DEFAULT 0x0007

//PHY Identifier 2 register
#define LAN8720_PHYID2_PHY_ID_LSB         0xFC00
#define LAN8720_PHYID2_PHY_ID_LSB_DEFAULT 0xC000
#define LAN8720_PHYID2_MODEL_NUM          0x03F0
#define LAN8720_PHYID2_MODEL_NUM_DEFAULT  0x00F0
#define LAN8720_PHYID2_REVISION_NUM       0x000F

//Auto-Negotiation Advertisement register
#define LAN8720_ANAR_REMOTE_FAULT         0x2000
#define LAN8720_ANAR_PAUSE                0x0C00
#define LAN8720_ANAR_100BTX_FD            0x0100
#define LAN8720_ANAR_100BTX_HD            0x0080
#define LAN8720_ANAR_10BT_FD              0x0040
#define LAN8720_ANAR_10BT_HD              0x0020
#define LAN8720_ANAR_SELECTOR             0x001F
#define LAN8720_ANAR_SELECTOR_DEFAULT     0x0001

//Auto-Negotiation Link Partner Ability register
#define LAN8720_ANLPAR_NEXT_PAGE          0x8000
#define LAN8720_ANLPAR_ACK                0x4000
#define LAN8720_ANLPAR_REMOTE_FAULT       0x2000
#define LAN8720_ANLPAR_PAUSE              0x0400
#define LAN8720_ANLPAR_100BT4             0x0200
#define LAN8720_ANLPAR_100BTX_FD          0x0100
#define LAN8720_ANLPAR_100BTX_HD          0x0080
#define LAN8720_ANLPAR_10BT_FD            0x0040
#define LAN8720_ANLPAR_10BT_HD            0x0020
#define LAN8720_ANLPAR_SELECTOR           0x001F
#define LAN8720_ANLPAR_SELECTOR_DEFAULT   0x0001

//Auto-Negotiation Expansion register
#define LAN8720_ANER_PAR_DETECT_FAULT     0x0010
#define LAN8720_ANER_LP_NEXT_PAGE_ABLE    0x0008
#define LAN8720_ANER_NEXT_PAGE_ABLE       0x0004
#define LAN8720_ANER_PAGE_RECEIVED        0x0002
#define LAN8720_ANER_LP_AN_ABLE           0x0001

//Mode Control/Status register
#define LAN8720_MCSR_EDPWRDOWN            0x2000
#define LAN8720_MCSR_FARLOOPBACK          0x0200
#define LAN8720_MCSR_ALTINT               0x0040
#define LAN8720_MCSR_ENERGYON             0x0002

//Special Modes register
#define LAN8720_SMR_MODE                  0x00E0
#define LAN8720_SMR_PHYAD                 0x001F

//Symbol Error Counter register
#define LAN8720_SECR_SYM_ERR_CNT          0xFFFF

//Special Control/Status Indication register
#define LAN8720_SCSIR_AMDIXCTRL           0x8000
#define LAN8720_SCSIR_CH_SELECT           0x2000
#define LAN8720_SCSIR_SQEOFF              0x0800
#define LAN8720_SCSIR_XPOL                0x0010

//Interrupt Source register
#define LAN8720_ISR_ENERGYON              0x0080
#define LAN8720_ISR_AN_COMPLETE           0x0040
#define LAN8720_ISR_REMOTE_FAULT          0x0020
#define LAN8720_ISR_LINK_DOWN             0x0010
#define LAN8720_ISR_AN_LP_ACK             0x0008
#define LAN8720_ISR_PAR_DETECT_FAULT      0x0004
#define LAN8720_ISR_AN_PAGE_RECEIVED      0x0002

//Interrupt Mask register
#define LAN8720_IMR_ENERGYON              0x0080
#define LAN8720_IMR_AN_COMPLETE           0x0040
#define LAN8720_IMR_REMOTE_FAULT          0x0020
#define LAN8720_IMR_LINK_DOWN             0x0010
#define LAN8720_IMR_AN_LP_ACK             0x0008
#define LAN8720_IMR_PAR_DETECT_FAULT      0x0004
#define LAN8720_IMR_AN_PAGE_RECEIVED      0x0002

//PHY Special Control/Status register
#define LAN8720_PSCSR_AUTODONE            0x1000
#define LAN8720_PSCSR_HCDSPEED            0x001C
#define LAN8720_PSCSR_HCDSPEED_10BT_HD    0x0004
#define LAN8720_PSCSR_HCDSPEED_100BTX_HD  0x0008
#define LAN8720_PSCSR_HCDSPEED_10BT_FD    0x0014
#define LAN8720_PSCSR_HCDSPEED_100BTX_FD  0x0018



// Datasheet: http://ww1.microchip.com/downloads/en/devicedoc/00002165b.pdf
// SMI Protocol: Section 3.5, Page 23
// SMI Registers: Section 4.2, Page 42

// More code: https://www.oryx-embedded.com/doc/lan8720__driver_8c_source.html

void inline smi_sendclock(uint8_t bit) {
  digitalWrite(smi_clock, bit);
  delayMicroseconds(CLK_DELAY_MICROS);
}

void inline smi_sendbit(uint8_t bit) {
  digitalWrite(smi_data, bit);
  delayMicroseconds(CLK_DELAY_MICROS);
  smi_sendclock(1);
  smi_sendclock(0);
}

void serial_print_bin(char *prefix, uint16_t value) {
  Serial.print(prefix);
  Serial.print("=");
  for (int b = 15; b >= 0; b--) {
    if (value & (1 << b)) {
      Serial.print("1 ");
    } else {
      Serial.print("0 ");
    }
  }
  //  Serial.print(value, BIN);
  //  Serial.print("");
}

uint8_t inline smi_readbit() {
  delayMicroseconds(CLK_DELAY_MICROS);
  uint8_t bit = digitalRead(smi_data);
  smi_sendclock(1);
  smi_sendclock(0);
  return bit;
}

void smi_poke(uint8_t phy_address, uint8_t register_address, uint16_t value) {
  pinMode(smi_data, OUTPUT);

  digitalWrite(smi_data, 0);
  digitalWrite(smi_clock, 0);

  // Preamble
  for (int i = 0; i < 32; i++) {
    smi_sendbit(1);
  }

  // Start signal
  smi_sendbit(0);
  smi_sendbit(1);

  // OP Code
  smi_sendbit(0);
  smi_sendbit(1);

  // PHY Address
  for (int b = 4; b >= 0; b--) {
    smi_sendbit(phy_address & (1 << b));
  }

  // Register Address
  for (int b = 4; b >= 0; b--) {
    smi_sendbit(register_address & (1 << b));
  }

  digitalWrite(smi_data, 1);

  // Turnaround
  smi_sendclock(1);
  smi_sendclock(0);

  digitalWrite(smi_data, 0);

  smi_sendclock(1);
  smi_sendclock(0);

  // Write data
  for (int b = 15; b >= 0; b--) {
    smi_sendbit(value & (1 << b));
  }

  digitalWrite(smi_data, 0);
  digitalWrite(smi_clock, 0);

  pinMode(smi_data, OUTPUT);

  delay(1);
}

uint16_t smi_peek(uint8_t phy_address, uint8_t register_address) {
  uint16_t output = 0;

  pinMode(smi_data, OUTPUT);

  digitalWrite(smi_data, 0);
  digitalWrite(smi_clock, 0);

  // Preamble
  for (int i = 0; i < 32; i++) {
    smi_sendbit(1);
  }

  // Start signal
  smi_sendbit(0);
  smi_sendbit(1);

  // OP Code
  smi_sendbit(1);
  smi_sendbit(0);

  // PHY Address
  for (int b = 4; b >= 0; b--) {
    smi_sendbit(phy_address & (1 << b));
  }

  // Register Address
  for (int b = 4; b >= 0; b--) {
    smi_sendbit(register_address & (1 << b));
  }

  // Turnaround
  smi_sendclock(1);
  pinMode(smi_data, INPUT);
  smi_sendclock(0);
  smi_sendclock(1);
  smi_sendclock(0);

  // Write data
  for (int b = 15; b >= 0; b--) {
    uint8_t bit = smi_readbit();
    if (bit) output += (1 << b);
  }

  pinMode(smi_data, OUTPUT);

  digitalWrite(smi_data, 0);
  digitalWrite(smi_clock, 0);

  delay(1);

  return output;
}

// the setup routine runs once when you press reset:
void setup() {
  uint16_t dummy;

  // initialize the digital pin as an output.
  pinMode(txpin1, OUTPUT);
  pinMode(txpin2, OUTPUT);
  pinMode(txpen, OUTPUT);
  pinMode(powerpin, OUTPUT);

  pinMode(smi_clock, OUTPUT);
  pinMode(smi_data, OUTPUT);

  Serial.begin(57600);

  while (!Serial) {}
 
  delay(1000);

  Serial.print("Softresetting PHY\n");

  digitalWrite(powerpin, 1);

  // Soft reset
  smi_poke(phy_address, 0, 0x8000);
  do {
    dummy = smi_peek(phy_address, 0);
    serial_print_bin("status", dummy);
    Serial.print("\n");
    delay(10);
  } while(dummy & 0x8000);

  delay(100);

  // Disable 10mbit
  dummy = smi_peek(phy_address, 4);
  serial_print_bin("speed change read #4", dummy);
  Serial.print("\n");
  dummy &= ~(96); // bit 5 + 6
  serial_print_bin("speed change write #4", dummy);
  Serial.print("\n");
  smi_poke(phy_address, 4, dummy);
  do {
    dummy = smi_peek(phy_address, 4);
    serial_print_bin("speed change poll #4", dummy);
    Serial.print("\n");
    delay(100);
  } while ((dummy & 96) != 0);


  dummy = smi_peek(phy_address, 0);
  serial_print_bin("disable autoneg read #0", dummy);
  Serial.print("\n");
  // dummy = 0;
  dummy &= ~(1 << 12); // enable autonegotiaton
  //  dummy |= (1 << 9); // restart autoneg.
  serial_print_bin("disable autoneg write #0", dummy);
  Serial.print("\n");
  smi_poke(phy_address, 0, dummy);

//  do {
    dummy = smi_peek(phy_address, 0);
    serial_print_bin("disable autoneg poll #0", dummy);
    Serial.print("\n");
//    delay(100);
//  } while (!(dummy & (1 << 13)));
a

  dummy = smi_peek(phy_address, 0);
  serial_print_bin("set speed read #0", dummy);
  Serial.print("\n");
  // dummy = 0;
  dummy |= (1 << 13); // 100mbit
  dummy &= ~(1 << 10); // isolate?
  dummy |= (1 << 8); // full duplex
  //  dummy |= (1 << 9); // restart autoneg.
  serial_print_bin("set speed write #0", dummy);
  Serial.print("\n");
  smi_poke(phy_address, 0, dummy);
//  do {
    dummy = smi_peek(phy_address, 0);
    serial_print_bin("set speed poll #0", dummy);
    Serial.print("\n");
//    delay(100);
//  } while (!(dummy & (1 << 13)));

//
//  dummy = smi_peek(phy_address, 0);
//  serial_print_bin("restart autoneg read #0", dummy);
//  Serial.print("\n");
//  dummy |= (1 << 9); // restart autoneg.
//  serial_print_bin("restart autoneg write #0", dummy);
//  Serial.print("\n");
//  smi_poke(phy_address, 0, dummy);
//  do {
//    dummy = smi_peek(phy_address, 0);
//    serial_print_bin("restart autoneg poll #4", dummy);
//    Serial.print("\n");
//    delay(100);
//  } while (dummy & (1 << 9));

  //    smi_poke(phy_address, LAN8720_IMR, LAN8720_IMR_AN_COMPLETE |
  //       LAN8720_IMR_LINK_DOWN);
  //

  //  dummy = smi_peek(phy_address, 0);
  //  dummy &= ~(1 << 12); // disable autonegotiaton
  //  dummy |= (1 << 13); // 100mbit
  //  dummy &= ~(1 << 8); // half duplex
  //  smi_poke(phy_address, 0, dummy);

  //  restart auto-neg.
  //    dummy = 1 << 9;
  //    smi_poke(phy_address, 0, dummy);

  //  do {
  //    dummy = smi_peek(phy_address, 0);
  //    Serial.print("Waiting for reset status=");
  //    Serial.print(dummy);
  //    Serial.print("\n");
  //    delay(100);
  //  } while(dummy & 0x8000);

  for (int k = 0; k < 31; k++) {
    dummy = smi_peek(phy_address, k);
    Serial.print("register #");
    Serial.print(k, DEC);
    serial_print_bin(" value", dummy);
    Serial.print("\n");
  }
  Serial.print("\n");
}

uint16_t laststatus = 9999;
uint32_t nextcheck = 0;
uint8_t lastlinkstatus = 4;

// the loop routine runs over and over again forever:
void loop() {
  uint16_t dummy;
  uint16_t status;
  uint8_t linkstatus;

  for (int i = 0; i < 1000; i++) {
    digitalWrite(txpin1, rand() & 1); // (counter & 2) == 2);
    digitalWrite(txpin2, rand() & 1); // (counter & 2) == 2);
    digitalWrite(txpen, 1);
    digitalWrite(txpen, 0);
  }
  uint32_t T = millis();
  if (T > nextcheck) {
    nextcheck = T + 200;

    status = smi_peek(phy_address, 1);
    status = smi_peek(phy_address, 1);

    if (status != laststatus) {
      laststatus = status;

      //    Serial.print("status=");
      //    Serial.print(status, BIN);
      serial_print_bin("status", status);
      Serial.print("\n");
      linkstatus = (status & LAN8720_BMSR_LINK_STATUS) != 0;
      Serial.print("ext cap.=");
      Serial.print((status & 1) != 0);
      Serial.print("\n");
      Serial.print("jabber detect=");
      Serial.print((status & 2) != 0);
      Serial.print("\n");
      Serial.print("link status=");
      Serial.print(linkstatus);
      Serial.print("\n");
      Serial.print("auto negotiate ability=");
      Serial.print((status & 8) != 0);
      Serial.print("\n");
      Serial.print("remote fault=");
      Serial.print((status & 16) != 0);
      Serial.print("\n");
      Serial.print("auto negotiate complete=");
      Serial.print((status & 32) != 0);
      Serial.print("\n");
      //        Serial.print("=");
      //        Serial.print((status & 64) != 0);
      //        Serial.print("\n");

      dummy = smi_peek(phy_address, LAN8720_PSCSR);

      if (status & LAN8720_BMSR_LINK_STATUS) {
        //      Serial.print("LAN8720_PSCSR=");
        //      Serial.print(dummy, BIN);
        serial_print_bin("LAN8720_PSCSR", dummy);
        Serial.print("\n");

        switch (dummy & LAN8720_PSCSR_HCDSPEED)
        {
          case LAN8720_PSCSR_HCDSPEED_10BT_HD:
            Serial.print("10BASE-T half-duplex\n");
            break;
          case LAN8720_PSCSR_HCDSPEED_10BT_FD:
            Serial.print("10BASE-T full-duplex\n");
            break;
          case LAN8720_PSCSR_HCDSPEED_100BTX_HD:
            Serial.print("100BASE-TX half-duplex\n");
            break;
          case LAN8720_PSCSR_HCDSPEED_100BTX_FD:
            Serial.print("100BASE-TX full-duplex\n");
            break;
          default:
            Serial.print("Invalid mode\n");
            break;
        }
      } else {
        Serial.print("No link\n");
      }

      dummy = smi_peek(phy_address, 4);
      serial_print_bin("#4", dummy);
      Serial.print("\n");

      dummy = smi_peek(phy_address, 5);
      serial_print_bin("#5", dummy);
      Serial.print("\n");

      if (linkstatus != lastlinkstatus) {
        lastlinkstatus = linkstatus;
        // trigger autonegotiation
        if (linkstatus) {
//          Serial.print("Re-trigger autonegotiation?\n");

//          dummy = smi_peek(phy_address, 0);
//          serial_print_bin("autoneg read #0", dummy);
//          Serial.print("\n");
//          //    dummy = 0;
//          //    dummy |= (1 << 12); // enable autonegotiaton
//          //    dummy |= (1 << 13); // 100mbit
//          //    dummy |= (1 << 10); // isolate?
//          dummy |= (1 << 9); // restart autoneg.
          //    dummy |= (1 << 8); // full duplex
          //    serial_print_bin("autoneg write #0", dummy);
          //    Serial.print("\n");
          //    smi_poke(phy_address, 0, dummy);
          //    do {
          //      dummy = smi_peek(phy_address, 0);
          //      serial_print_bin("autoneg poll #4", dummy);
          //      Serial.print("\n");
          //      delay(100);
          //    } while(dummy & (1 << 9));

        }
      }

      Serial.print("\n");
      // }
    }
  }
  //  delayMicroseconds(10);
  counter ++;
}