diff --git a/sysmoOCTSIM/hal/include/hpl_i2c_s_sync.h b/sysmoOCTSIM/hal/include/hpl_i2c_s_sync.h
new file mode 100644
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+++ b/sysmoOCTSIM/hal/include/hpl_i2c_s_sync.h
@@ -0,0 +1,184 @@
+/**
+ * \file
+ *
+ * \brief I2C Slave Hardware Proxy Layer(HPL) declaration.
+ *
+ * Copyright (c) 2015-2018 Microchip Technology Inc. and its subsidiaries.
+ *
+ * \asf_license_start
+ *
+ * \page License
+ *
+ * Subject to your compliance with these terms, you may use Microchip
+ * software and any derivatives exclusively with Microchip products.
+ * It is your responsibility to comply with third party license terms applicable
+ * to your use of third party software (including open source software) that
+ * may accompany Microchip software.
+ *
+ * THIS SOFTWARE IS SUPPLIED BY MICROCHIP "AS IS". NO WARRANTIES,
+ * WHETHER EXPRESS, IMPLIED OR STATUTORY, APPLY TO THIS SOFTWARE,
+ * INCLUDING ANY IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY,
+ * AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT WILL MICROCHIP BE
+ * LIABLE FOR ANY INDIRECT, SPECIAL, PUNITIVE, INCIDENTAL OR CONSEQUENTIAL
+ * LOSS, DAMAGE, COST OR EXPENSE OF ANY KIND WHATSOEVER RELATED TO THE
+ * SOFTWARE, HOWEVER CAUSED, EVEN IF MICROCHIP HAS BEEN ADVISED OF THE
+ * POSSIBILITY OR THE DAMAGES ARE FORESEEABLE.  TO THE FULLEST EXTENT
+ * ALLOWED BY LAW, MICROCHIP'S TOTAL LIABILITY ON ALL CLAIMS IN ANY WAY
+ * RELATED TO THIS SOFTWARE WILL NOT EXCEED THE AMOUNT OF FEES, IF ANY,
+ * THAT YOU HAVE PAID DIRECTLY TO MICROCHIP FOR THIS SOFTWARE.
+ *
+ * \asf_license_stop
+ *
+ */
+#ifndef _HPL_I2C_S_SYNC_H_INCLUDED
+#define _HPL_I2C_S_SYNC_H_INCLUDED
+
+#include <compiler.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \brief I2C Slave status type
+ */
+typedef uint32_t i2c_s_status_t;
+
+/**
+ * \brief i2c slave device structure
+ */
+struct _i2c_s_sync_device {
+	void *hw;
+};
+
+#include <compiler.h>
+
+/**
+ * \name HPL functions
+ */
+
+/**
+ * \brief Initialize synchronous I2C slave
+ *
+ * This function does low level I2C configuration.
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ *
+ * \return Return 0 for success and negative value for error
+ */
+int32_t _i2c_s_sync_init(struct _i2c_s_sync_device *const device, void *const hw);
+
+/**
+ * \brief Deinitialize synchronous I2C slave
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ *
+ * \return Return 0 for success and negative value for error
+ */
+int32_t _i2c_s_sync_deinit(struct _i2c_s_sync_device *const device);
+
+/**
+ * \brief Enable I2C module
+ *
+ * This function does low level I2C enable.
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ *
+ * \return Return 0 for success and negative value for error
+ */
+int32_t _i2c_s_sync_enable(struct _i2c_s_sync_device *const device);
+
+/**
+ * \brief Disable I2C module
+ *
+ * This function does low level I2C disable.
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ *
+ * \return Return 0 for success and negative value for error
+ */
+int32_t _i2c_s_sync_disable(struct _i2c_s_sync_device *const device);
+
+/**
+ * \brief Check if 10-bit addressing mode is on
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ *
+ * \return Cheking status
+ * \retval 1 10-bit addressing mode is on
+ * \retval 0 10-bit addressing mode is off
+ */
+int32_t _i2c_s_sync_is_10bit_addressing_on(const struct _i2c_s_sync_device *const device);
+
+/**
+ * \brief Set I2C slave address
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ * \param[in] address Address to set
+ *
+ * \return Return 0 for success and negative value for error
+ */
+int32_t _i2c_s_sync_set_address(struct _i2c_s_sync_device *const device, const uint16_t address);
+
+/**
+ * \brief Write a byte to the given I2C instance
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ * \param[in] data Data to write
+ */
+void _i2c_s_sync_write_byte(struct _i2c_s_sync_device *const device, const uint8_t data);
+
+/**
+ * \brief Retrieve I2C slave status
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ *
+ *\return I2C slave status
+ */
+i2c_s_status_t _i2c_s_sync_get_status(const struct _i2c_s_sync_device *const device);
+
+/**
+ * \brief Clear the Data Ready interrupt flag
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ *
+ * \return Return 0 for success and negative value for error
+ */
+int32_t _i2c_s_sync_clear_data_ready_flag(const struct _i2c_s_sync_device *const device);
+
+/**
+ * \brief Read a byte from the given I2C instance
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ *
+ * \return Data received via I2C interface.
+ */
+uint8_t _i2c_s_sync_read_byte(const struct _i2c_s_sync_device *const device);
+
+/**
+ * \brief Check if I2C is ready to send next byte
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ *
+ * \return Status of the ready check.
+ * \retval true if the I2C is ready to send next byte
+ * \retval false if the I2C is not ready to send next byte
+ */
+bool _i2c_s_sync_is_byte_sent(const struct _i2c_s_sync_device *const device);
+
+/**
+ * \brief Check if there is data received by I2C
+ *
+ * \param[in] device The pointer to i2c slave device structure
+ *
+ * \return Status of the data received check.
+ * \retval true if the I2C has received a byte
+ * \retval false if the I2C has not received a byte
+ */
+bool _i2c_s_sync_is_byte_received(const struct _i2c_s_sync_device *const device);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _HPL_I2C_S_SYNC_H_INCLUDED */