diff --git a/variants/elbear_nano/pins_arduino.h b/variants/elbear_nano/pins_arduino.h
new file mode 100644
index 0000000..d531927
--- /dev/null
+++ b/variants/elbear_nano/pins_arduino.h
@@ -0,0 +1,142 @@
+/*
+  pins_arduino.h - Pin definition functions for Arduino
+  Part of Arduino - http://www.arduino.cc/
+
+  Copyright (c) 2007 David A. Mellis
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General
+  Public License along with this library; if not, write to the
+  Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+  Boston, MA  02111-1307  USA
+*/
+
+#ifndef Pins_Arduino_h
+#define Pins_Arduino_h
+
+#include "wiring_constants.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "mik32_hal_gpio.h"
+#include "mik32_hal_timer32.h"
+
+// analog pins
+#define PIN_A0        (14)
+#define PIN_A1        (15)
+#define PIN_A2        (16)
+#define PIN_A3        (17)
+#define PIN_A4        (18)
+#define PIN_A5        (19)
+#define PIN_A6        (20)
+#define PIN_A7        (21)
+static const uint8_t A0 = PIN_A0;
+static const uint8_t A1 = PIN_A1;
+static const uint8_t A2 = PIN_A2;
+static const uint8_t A3 = PIN_A3;
+static const uint8_t A4 = PIN_A4;
+static const uint8_t A5 = PIN_A5;
+static const uint8_t A6 = PIN_A5;
+static const uint8_t A7 = PIN_A5;
+
+
+// digital pins
+// D0...D13
+
+// User led and button
+#define LED_BUILTIN   (22)
+
+// determines the address of the port by the board pin number to which this pin belongs on the MCU
+GPIO_TypeDef* digitalPinToPort(uint32_t digPinNumber);     
+// determines the pin address inside the port by the board pin number
+HAL_PinsTypeDef digitalPinToBitMask(uint32_t digPinNumber);
+// total number of pins available for initialization
+uint16_t pinCommonQty(void);
+// the function returns a reference to the OUTPUT address of the GPIO register
+volatile uint32_t* portOutputRegister(GPIO_TypeDef* GPIO_x);
+// the function returns a reference to the STATE address of the GPIO register
+volatile uint32_t* portInputRegister(GPIO_TypeDef* GPIO_x);
+// the function initializes additional MCU pins depending on the specified pin number
+void additionalPinsInit(uint32_t PinNumber);
+
+// UART
+// available uarts quantity
+#define SERIAL_PORT_QTY 2
+
+// ADC
+#define MCU_ADC_RESOLUTION    12 // bits
+// determines the ADC channel number by the board pin number
+uint32_t analogInputToChannelNumber(uint32_t PinNumber);
+
+// PWM
+#define PWM_FREQUENCY_MAX         1000000 // Hz
+bool digitalPinHasPWM(uint8_t p);
+bool digitalPinPwmIsOn(uint8_t digitalPin); // use only if digitalPinHasPWM() == true
+// determines which timer the pin belongs to
+TIMER32_TypeDef* pwmPinToTimer(uint32_t digPinNumber);
+// determines which timer channel the pin belongs to
+HAL_TIMER32_CHANNEL_IndexTypeDef pwmPinToTimerChannel(uint32_t digPinNumber);
+
+// SPI
+#define PIN_SPI_SS    (10)
+#define PIN_SPI_MOSI  (11)
+#define PIN_SPI_MISO  (12)
+#define PIN_SPI_SCK   (13)
+static const uint8_t SS   = PIN_SPI_SS;
+static const uint8_t MOSI = PIN_SPI_MOSI;
+static const uint8_t MISO = PIN_SPI_MISO;
+static const uint8_t SCK  = PIN_SPI_SCK;
+// config SEL_NSS1 to replace D10 to different controller pin,
+// because pin 1.3 which is D10 by default is needed to spi 
+void spi_onBegin(void);
+void spi_onEnd(void);
+
+// I2C
+#define PIN_WIRE_SDA  (18)
+#define PIN_WIRE_SCL  (19)
+#define I2C_NUM       (1) // i2c number 1
+static const uint8_t SDA = PIN_WIRE_SDA;
+static const uint8_t SCL = PIN_WIRE_SCL;
+// available frequencies
+#define WIRE_FREQ_100K    100000
+#define WIRE_FREQ_400K    400000
+#define WIRE_FREQ_1000K   1000000
+
+// interrupts
+
+#define EXTERNAL_INTERRUPTS_QTY   7 // todo
+extern uint8_t interruptInfo[EXTERNAL_INTERRUPTS_QTY][3];
+// determines the board pin number by interrupt number
+#define interruptToDigitalPin(interruptNum)   (interruptInfo[interruptNum][0])
+// determines gpio interrupt line by interrupt number
+#define interruptToGpioIntLine(interruptNum)  ((uint8_t)interruptInfo[interruptNum][1])
+// determines gpio interrupt mux by interrupt number
+#define interruptToGpioIntMux(interruptNum)   ((uint8_t)interruptInfo[interruptNum][2])
+// determines interrupt number by the board pin number 
+int8_t digitalPinToInterrupt(uint32_t digPinNumber);
+// determines interrupt number by the gpio interrupt line
+int8_t gpioIntLineToInterrupt(uint32_t gpioIntLine);
+// determines gpio interrupt mux by the board pin number
+int8_t digitalPinToGpioIntMux(uint8_t digPinNumber);
+// determines gpio interrupt line by the board pin number
+int8_t digitalPinToGpioIntLine(uint8_t digPinNumber);
+
+
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/variants/elbear_nano/variant.c b/variants/elbear_nano/variant.c
new file mode 100644
index 0000000..473111e
--- /dev/null
+++ b/variants/elbear_nano/variant.c
@@ -0,0 +1,352 @@
+/**
+ *******************************************************************************
+ * Copyright (c) 2021 Nanjing Qinheng Microelectronics Co., Ltd.
+ * All rights reserved.
+ *
+ * This software component is licensed by WCH under BSD 3-Clause license,
+ * the "License"; You may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at:
+ *                        opensource.org/licenses/BSD-3-Clause
+ *
+ *******************************************************************************
+ */
+
+#include "pins_arduino.h"
+#include "mik32_hal_adc.h"
+#include "wiring_analog.h"
+#include "wiring_LL.h" 
+
+bool spiNssPinIsBlocked = false;
+
+// list of pin numbers from both ports with pins inside the port
+// todo аналоговые сигналы и SDA SCL!
+const HAL_PinsTypeDef digitalPinToGpioPinArray[] =
+{
+  GPIO_PIN_5, // D0
+  GPIO_PIN_6, // D1
+  GPIO_PIN_10,// D2
+  GPIO_PIN_0, // D3
+  GPIO_PIN_8, // D4
+  GPIO_PIN_1, // D5
+  GPIO_PIN_2, // D6
+  GPIO_PIN_8, // D7
+  GPIO_PIN_9, // D8
+  GPIO_PIN_3, // D9
+  GPIO_PIN_3, // D10
+  GPIO_PIN_1, // D11
+  GPIO_PIN_0, // D12
+  GPIO_PIN_2, // D13
+  GPIO_PIN_5, // D14/A0
+  GPIO_PIN_7, // D15/A1
+  GPIO_PIN_4, // D16/A2
+  GPIO_PIN_7, // D17/A3
+  GPIO_PIN_12,// D18/SDA
+  GPIO_PIN_13,// D19/SCL
+  GPIO_PIN_9, // A4
+  GPIO_PIN_9, // A5
+  GPIO_PIN_9, // A6
+  GPIO_PIN_9, // A7
+  GPIO_PIN_7, // LED(pin 22)  
+};
+
+// etermines the address of the port by the board pin number to which this pin belongs on the MCU
+// todo номера пинов А4...А7
+GPIO_TypeDef* digitalPinToPort(uint32_t digPinNumber)
+{
+  GPIO_TypeDef* gpioNum = 0;
+  // port 0 - board pins 0...6, 9, 16(A2), 17(A3), 20(A4), 21(A5)
+  if ((digPinNumber >= 0 && digPinNumber <= 6) || digPinNumber == 9 || digPinNumber == 16 
+      || digPinNumber == 17 || digPinNumber == 20 || digPinNumber == 21) // 12 pieces
+    gpioNum = GPIO_0;
+  // port 1 - board pins 7, 8, 10...13, 14(А0), 15(А1), 18,19
+  else if (digPinNumber == 7 || digPinNumber == 8 || (digPinNumber >= 10 && digPinNumber <= 15) 
+          || digPinNumber == 18 || digPinNumber == 19) // 10 pieces
+    gpioNum = GPIO_1;
+  // port 2 - led
+  else if (digPinNumber == LED_BUILTIN)
+    gpioNum = GPIO_2;
+
+  return gpioNum;
+}
+
+// determines the pin address inside the port by the board pin number
+HAL_PinsTypeDef digitalPinToBitMask(uint32_t digPinNumber)
+{
+  if (digPinNumber < pinCommonQty())
+  {
+    HAL_PinsTypeDef mask;
+    // if spi is on default pin 1.3 is needed for spi, D10 is replaced to pin 1.4
+    if (spiNssPinIsBlocked && (digPinNumber == 10))
+      mask = GPIO_PIN_4;
+    else 
+      mask = digitalPinToGpioPinArray[digPinNumber];
+    return mask;
+  }
+  else
+    return NC; 
+}
+
+uint16_t pinCommonQty(void)
+{
+  // todo так или меняем из-за А4...А7?
+  return (uint16_t)(sizeof(digitalPinToGpioPinArray)/sizeof(digitalPinToGpioPinArray[0]));
+}
+
+// the function returns a reference to the OUTPUT address of the GPIO register
+volatile uint32_t* portOutputRegister(GPIO_TypeDef* GPIO_x)
+{
+  return &GPIO_x->OUTPUT_;
+}
+
+// the function returns a reference to the STATE address of the GPIO register
+volatile uint32_t* portInputRegister(GPIO_TypeDef* GPIO_x)
+{
+  return &GPIO_x->STATE;
+}
+
+// the function initializes additional MCU pins depending on the specified pin number
+#define SELA_A_PORT   GPIO_1
+#define SELA_A_PIN    GPIO_PIN_15
+#define SELA_B_PORT   GPIO_1
+#define SELA_B_PIN    GPIO_PIN_11
+static bool selaSwitchesIsInited = false;
+
+void additionalPinsInit(uint32_t PinNumber)
+{
+  // init switches
+  if (!selaSwitchesIsInited)
+  {
+    // SELA_A
+    HAL_GPIO_PinConfig(SELA_A_PORT, SELA_A_PIN, HAL_GPIO_MODE_GPIO_OUTPUT, HAL_GPIO_PULL_NONE, HAL_GPIO_DS_2MA);
+    // SELA_B
+    HAL_GPIO_PinConfig(SELA_B_PORT, SELA_B_PIN, HAL_GPIO_MODE_GPIO_OUTPUT, HAL_GPIO_PULL_NONE, HAL_GPIO_DS_2MA);
+    selaSwitchesIsInited = true;
+  }
+  
+  if (PinNumber == A4)   
+  {
+    HAL_GPIO_WritePin(SELA_A_PORT, SELA_A_PIN, GPIO_PIN_LOW);
+    HAL_GPIO_WritePin(SELA_B_PORT, SELA_B_PIN, GPIO_PIN_LOW);
+  }
+  else if(PinNumber == A5)
+  {
+    HAL_GPIO_WritePin(SELA_A_PORT, SELA_A_PIN, GPIO_PIN_HIGH);
+    HAL_GPIO_WritePin(SELA_B_PORT, SELA_B_PIN, GPIO_PIN_LOW);
+  }
+  else if(PinNumber == A6)
+  {
+    HAL_GPIO_WritePin(SELA_A_PORT, SELA_A_PIN, GPIO_PIN_LOW);
+    HAL_GPIO_WritePin(SELA_B_PORT, SELA_B_PIN, GPIO_PIN_HIGH);
+  }
+  else if(PinNumber == A7)
+  {
+    HAL_GPIO_WritePin(SELA_A_PORT, SELA_A_PIN, GPIO_PIN_HIGH);
+    HAL_GPIO_WritePin(SELA_B_PORT, SELA_B_PIN, GPIO_PIN_HIGH);
+  }
+}
+
+// ---------------------- ADC ---------------------- //
+// determines the ADC channel number by the board pin number
+uint32_t analogInputToChannelNumber(uint32_t PinNumber)
+{
+  uint32_t adcChannel = 0;
+
+  // if get a value 0...5 instead of A0...A5
+  if (PinNumber < 4) PinNumber += 14;
+  // todo проверить
+  else if (PinNumber < 6) PinNumber += 16;
+
+  switch (PinNumber)
+  {
+    case PIN_A0:
+      adcChannel = ADC_CHANNEL0;
+      break;
+    case PIN_A1:
+      adcChannel = ADC_CHANNEL1;
+      break;
+    case PIN_A2:
+      adcChannel = ADC_CHANNEL3;
+      break;
+    case PIN_A3:
+      adcChannel = ADC_CHANNEL4;
+      break;
+    case PIN_A4:
+    case PIN_A5:
+    case PIN_A6:
+    case PIN_A7:
+      adcChannel = ADC_CHANNEL5;
+      break;
+    default:
+      adcChannel = NC;
+  }
+  return adcChannel;
+}
+
+// ---------------------- PWM ---------------------- //
+// use only if digitalPinHasPWM() == true
+// todo еще D12, D13? 
+#define PWM_PIN_TO_PORT_NUMBER(pin)           (((pin==10)||(pin==11)) ? 1:0)
+// use only if digitalPinHasPWM() == true
+static inline uint8_t pwmPinToGpioPinShift(uint8_t digitalPin)
+{
+  // todo еще D12, D13? 
+  if (digitalPin == 3)
+    return 0;
+  else if ((digitalPin == 5) || (digitalPin == 11))
+    return 1;
+  else if (digitalPin == 6)
+    return 2;
+  else // pins 9 10
+    return 3; 
+}
+// use only if digitalPinHasPWM() == true
+// return true if digitalPin configured as pwm
+bool digitalPinPwmIsOn(uint8_t digitalPin)
+{
+  uint8_t config = 0;
+  uint8_t pinShift = pwmPinToGpioPinShift(digitalPin);
+
+  if (PWM_PIN_TO_PORT_NUMBER(digitalPin) == 0)
+    config = PIN_GET_PAD_CONFIG(PORT_0_CFG, pinShift);
+  else 
+    config = PIN_GET_PAD_CONFIG(PORT_1_CFG, pinShift);
+
+  if (config == 2)
+    return true;
+  else
+    return false;
+}
+
+bool digitalPinHasPWM(uint8_t p)   
+{
+  bool ret = false;
+  // if spi is in use D10 cannot work as pwm
+  if (spiNssPinIsBlocked && (p == 10))
+    ret = false;
+  else if ((p) == 3 || (p) == 5 || (p) == 6 || (p) == 9 || (p) == 10 || (p) == 11)
+    ret = true;
+  return ret;
+}
+
+// function is used only if digitalPinHasPWM() is true
+TIMER32_TypeDef* pwmPinToTimer(uint32_t digPinNumber)
+{
+  TIMER32_TypeDef* timerNum = NULL;
+
+  // timer 1
+  if (digPinNumber == 3 || digPinNumber == 5 || digPinNumber == 6 || digPinNumber == 9)
+    timerNum = TIMER32_1;
+  // timer 2
+  else if (digPinNumber == 10 || digPinNumber == 11)
+    timerNum = TIMER32_2;
+  
+  return timerNum;
+}
+
+// function is used only if digitalPinHasPWM() is true
+HAL_TIMER32_CHANNEL_IndexTypeDef pwmPinToTimerChannel(uint32_t digPinNumber)
+{
+  HAL_TIMER32_CHANNEL_IndexTypeDef channel = 0;
+  if      (digPinNumber == 3)                         channel = TIMER32_CHANNEL_0;
+  else if (digPinNumber == 5 || digPinNumber == 11)   channel = TIMER32_CHANNEL_1;
+  else if (digPinNumber == 6)                         channel = TIMER32_CHANNEL_2;
+  else if (digPinNumber == 9 || digPinNumber == 10)   channel = TIMER32_CHANNEL_3;
+  return channel;
+}
+
+// ---------------------- interrupts ---------------------- //
+// interrupt table is stored in ram to improve performance
+// index = interrupt number. In each row {digitalPinNumber, IntLineValue, IntMuxValue}
+uint8_t interruptInfo[EXTERNAL_INTERRUPTS_QTY][3] = 
+{
+  { 2,      GPIO_LINE_2,  GPIO_MUX_LINE_2_PORT0_10},  // INT0
+  { 3,      GPIO_LINE_0,  GPIO_MUX_LINE_0_PORT0_0},   // INT1
+  { 4,      GPIO_LINE_4,  GPIO_MUX_LINE_4_PORT0_8},   // INT2
+  { 5,      GPIO_LINE_1,  GPIO_MUX_LINE_1_PORT0_1},   // INT3
+  { 6,      GPIO_LINE_6,  GPIO_MUX_LINE_6_PORT0_2},   // INT4
+  { 8,      GPIO_LINE_5,  GPIO_MUX_LINE_5_PORT1_9},   // INT5
+  { 9,      GPIO_LINE_3,  GPIO_MUX_LINE_3_PORT0_3},   // INT6
+  { A1,     GPIO_LINE_7,  GPIO_MUX_LINE_7_PORT1_7},   // INT7
+};
+
+int8_t digitalPinToGpioIntMux(uint8_t digPinNumber)
+{
+  for (uint8_t i = 0; i < EXTERNAL_INTERRUPTS_QTY; i++)
+  {
+    if (interruptInfo[i][0] == digPinNumber)
+      return interruptInfo[i][2];
+  }
+  return NOT_AN_INTERRUPT;
+}
+int8_t digitalPinToGpioIntLine(uint8_t digPinNumber)
+{
+  for (uint8_t i = 0; i < EXTERNAL_INTERRUPTS_QTY; i++)
+  {
+    if (interruptInfo[i][0] == digPinNumber)
+      return interruptInfo[i][1];
+  }
+  return NOT_AN_INTERRUPT;
+}
+
+int8_t gpioIntLineToInterrupt(uint32_t gpioIntLine)
+{
+  for (uint8_t i = 0; i < EXTERNAL_INTERRUPTS_QTY; i++)
+  {
+    if (interruptInfo[i][1] == gpioIntLine)
+      return i;
+  }
+  return NOT_AN_INTERRUPT;
+}
+
+int8_t digitalPinToInterrupt(uint32_t digPinNumber)
+{
+  for (uint8_t i = 0; i < EXTERNAL_INTERRUPTS_QTY; i++)
+  {
+    if (interruptInfo[i][0] == digPinNumber)
+      return i;
+  }
+  return NOT_AN_INTERRUPT;
+}
+
+// ---------------------- SPI ---------------------- //
+void spi_onBegin(void)
+{
+  // On Elbear Nano there is a seller on pin 1.6 which replace D10 from spi NSS pin 1.3 to pin 1.4, 
+  // because spi needs pin 1.3 for correct work
+
+  // replace config from 1.3 to 1.4 
+  uint8_t config = PIN_GET_PAD_CONFIG(PORT_1_CFG, PIN_MASK_TO_PIN_NUMBER(GPIO_PIN_3));
+  if (config == 0)    // common gpio
+  {
+    // get info from pin gpio1.3 and set config to gpio1.4
+    HAL_GPIO_PinConfig(GPIO_1, GPIO_PIN_4, HAL_GPIO_GetPinDirection(GPIO_1, GPIO_PIN_3), 
+                      (HAL_GPIO_PullTypeDef)PIN_GET_PAD_CONFIG(PORT_1_PUPD, PIN_MASK_TO_PIN_NUMBER(GPIO_PIN_3)), 
+                      HAL_GPIO_DS_2MA);
+    HAL_GPIO_WritePin(GPIO_1, GPIO_PIN_4, (GPIO_PinState)GPIO_GET_PIN_STATE(GPIO_1, PIN_MASK_TO_PIN_NUMBER(GPIO_PIN_3)));
+    
+    // pin D10 was switched to different gpio and can be used further
+  }
+  else if(config == 2)  // timer for pwm
+  {
+    // if D10 (spi NSS pin) was used as pwm, we need to stop timer, because 1.4 doesn't support it
+    analogWriteStop(10);
+    ErrorMsgHandler("analogWrite(): D10 cannot be used as PWM pin while SPI is running");
+  }
+  
+  // switch seller to pin 1.4
+  HAL_GPIO_PinConfig(GPIO_1, GPIO_PIN_6, HAL_GPIO_MODE_GPIO_OUTPUT, HAL_GPIO_PULL_NONE, HAL_GPIO_DS_2MA);
+  HAL_GPIO_WritePin(GPIO_1, GPIO_PIN_6, GPIO_PIN_HIGH);
+  spiNssPinIsBlocked = true; // block spi pin
+}
+
+void spi_onEnd(void)
+{
+  // get info from pin gpio1.4 and set config to gpio1.3
+  HAL_GPIO_PinConfig(GPIO_1, GPIO_PIN_3, HAL_GPIO_GetPinDirection(GPIO_1, GPIO_PIN_4), 
+                      (HAL_GPIO_PullTypeDef)PIN_GET_PAD_CONFIG(PORT_1_PUPD, PIN_MASK_TO_PIN_NUMBER(GPIO_PIN_4)), HAL_GPIO_DS_2MA);
+  HAL_GPIO_WritePin(GPIO_1, GPIO_PIN_3,  (GPIO_PinState)GPIO_GET_PIN_STATE(GPIO_1, PIN_MASK_TO_PIN_NUMBER(GPIO_PIN_4)));
+
+  // switch seller back to pin 1.3
+  HAL_GPIO_WritePin(GPIO_1, GPIO_PIN_6, GPIO_PIN_LOW);
+  spiNssPinIsBlocked = false; // unblock spi pin
+}
\ No newline at end of file