Problem in jumping from application to bootloader

Question

Dear team, Device - nRF52832 SDK - SDK_15.0.0 IDE - Segger Embedded studio Softdevice - s132_nrf52_6.0.0 I am doing buttonless DFU in my application. I have successfully build the secure bootloader code and also jump from bootloader to application by following your guidelines. 
 The problem is that When i tried to jump from application to bootloader it causes "GATT connection timeout" error. I have seen this error in nrfconnect android application. But when i remove "CONFIG_AS_GPIO_PINRESET" macro in both codes bootloader and application then everything works perfectly. I don't want to remove this macro but want some another solution . Please guide me on the same. Your quick reply would be highly appreciated. Thanks.

Prajapati · Accepted Answer

Fullscreen ble_dfu_unbonded.c Download /** * Copyright (c) 2017 - 2018, Nordic Semiconductor ASA * * All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, * are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * 2. Redistributions in binary form, except as embedded into a Nordic * Semiconductor ASA integrated circuit in a product or a software update for * such product, must reproduce the above copyright notice, this list of * conditions and the following disclaimer in the documentation and/or other * materials provided with the distribution. * * 3. Neither the name of Nordic Semiconductor ASA nor the names of its * contributors may be used to endorse or promote products derived from this * software without specific prior written permission. * * 4. This software, with or without modification, must only be used with a * Nordic Semiconductor ASA integrated circuit. * * 5. Any software provided in binary form under this license must not be reverse * engineered, decompiled, modified and/or disassembled. * * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ #include #include #include #include "nrf_dfu_ble_svci_bond_sharing.h" #include "nordic_common.h" #include "nrf_error.h" #include "ble_dfu.h" #include "nrf_log.h" #include "nrf_sdh_soc.h" #include "nrf_gpio.h" #include "nrf_delay.h" #if (!NRF_DFU_BLE_BUTTONLESS_SUPPORTS_BONDS) #define NRF_DFU_ADV_NAME_MAX_LENGTH (20) void ble_dfu_buttonless_on_sys_evt(uint32_t, void * ); uint32_t nrf_dfu_svci_vector_table_set(void); uint32_t nrf_dfu_svci_vector_table_unset(void); /**@brief Define functions for async interface to set new advertisement name for DFU mode. */ NRF_SVCI_ASYNC_FUNC_DEFINE(NRF_DFU_SVCI_SET_ADV_NAME, nrf_dfu_set_adv_name, nrf_dfu_adv_name_t); // Register SoC observer for the Buttonless Secure DFU service NRF_SDH_SOC_OBSERVER(m_dfu_buttonless_soc_obs, BLE_DFU_SOC_OBSERVER_PRIO, ble_dfu_buttonless_on_sys_evt, NULL); ble_dfu_buttonless_t * mp_dfu = NULL; static nrf_dfu_adv_name_t m_adv_name; //extern bool ResetPinDisable; /**@brief Function for setting an advertisement name. * * @param[in] adv_name The new advertisement name. * * @retval NRF_SUCCESS Advertisement name was successfully set. * @retval DFU_RSP_BUSY Advertisement name was not set because of an ongoing operation. * @retval Any other errors from the SVCI interface call. */ static uint32_t set_adv_name(nrf_dfu_adv_name_t * p_adv_name) { uint32_t err_code; if (mp_dfu->is_waiting_for_svci) { return DFU_RSP_BUSY; } err_code = nrf_dfu_set_adv_name(p_adv_name); if (err_code == NRF_SUCCESS) { // The request was accepted. mp_dfu->is_waiting_for_svci = true; } else if (err_code == NRF_ERROR_FORBIDDEN) { NRF_LOG_ERROR("The bootloader has write protected its settings page. This prohibits setting the advertising name. "\ "The bootloader must be compiled with NRF_BL_SETTINGS_PAGE_PROTECT=0 to allow setting the advertising name."); } return err_code; } /**@brief Function for entering the bootloader. */ static uint32_t enter_bootloader() { uint32_t err_code; if (mp_dfu->is_waiting_for_svci) { // We have an ongoing async operation. Entering bootloader mode is not possible at this time. err_code = ble_dfu_buttonless_resp_send(DFU_OP_ENTER_BOOTLOADER, DFU_RSP_BUSY); if (err_code != NRF_SUCCESS) { mp_dfu->evt_handler(BLE_DFU_EVT_RESPONSE_SEND_ERROR); } return NRF_SUCCESS; } // Set the flag indicating that we expect DFU mode. // This will be handled on acknowledgement of the characteristic indication. mp_dfu->is_waiting_for_reset = true; err_code = ble_dfu_buttonless_resp_send(DFU_OP_ENTER_BOOTLOADER, DFU_RSP_SUCCESS); if (err_code != NRF_SUCCESS) { mp_dfu->is_waiting_for_reset = false; } return err_code; } uint32_t ble_dfu_buttonless_backend_init(ble_dfu_buttonless_t * p_dfu) { VERIFY_PARAM_NOT_NULL(p_dfu); mp_dfu = p_dfu; return NRF_SUCCESS; } uint32_t ble_dfu_buttonless_async_svci_init(void) { uint32_t ret_val; ret_val = nrf_dfu_svci_vector_table_set(); VERIFY_SUCCESS(ret_val); ret_val = nrf_dfu_set_adv_name_init(); VERIFY_SUCCESS(ret_val); ret_val = nrf_dfu_svci_vector_table_unset(); return ret_val; } void ble_dfu_buttonless_on_sys_evt(uint32_t sys_evt, void * p_context) { uint32_t err_code; if (!nrf_dfu_set_adv_name_is_initialized()) { return; } err_code = nrf_dfu_set_adv_name_on_sys_evt(sys_evt); if (err_code == NRF_ERROR_INVALID_STATE) { // The system event is not from an operation started by buttonless DFU. // No action is taken, and nothing is reported. } else if (err_code == NRF_SUCCESS) { // The async operation is finished. // Set the flag indicating that we are waiting for indication response // to activate the reset. mp_dfu->is_waiting_for_svci = false; // Report back the positive response err_code = ble_dfu_buttonless_resp_send(DFU_OP_SET_ADV_NAME, DFU_RSP_SUCCESS); if (err_code != NRF_SUCCESS) { mp_dfu->evt_handler(BLE_DFU_EVT_RESPONSE_SEND_ERROR); } } else { // Invalid error code reported back. mp_dfu->is_waiting_for_svci = false; err_code = ble_dfu_buttonless_resp_send(DFU_OP_SET_ADV_NAME, DFU_RSP_BUSY); if (err_code != NRF_SUCCESS) { mp_dfu->evt_handler(BLE_DFU_EVT_RESPONSE_SEND_ERROR); } // Report the failure to enter DFU mode mp_dfu->evt_handler(BLE_DFU_EVT_BOOTLOADER_ENTER_FAILED); } } uint32_t ble_dfu_buttonless_char_add(ble_dfu_buttonless_t * p_dfu) { ble_gatts_char_md_t char_md = {{0}}; ble_gatts_attr_md_t cccd_md = {{0}}; ble_gatts_attr_t attr_char_value = {0}; ble_gatts_attr_md_t attr_md = {{0}}; ble_uuid_t char_uuid; BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.read_perm); BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.write_perm); cccd_md.vloc = BLE_GATTS_VLOC_STACK; char_md.char_props.indicate = 1; char_md.char_props.write = 1; char_md.p_char_user_desc = NULL; char_md.p_char_pf = NULL; char_md.p_user_desc_md = NULL; char_md.p_cccd_md = &cccd_md; char_md.p_sccd_md = NULL; char_uuid.type = p_dfu->uuid_type; char_uuid.uuid = BLE_DFU_BUTTONLESS_CHAR_UUID; BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm); BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.write_perm); attr_md.vloc = BLE_GATTS_VLOC_STACK; attr_md.rd_auth = 0; attr_md.wr_auth = 1; attr_md.vlen = 1; attr_char_value.p_uuid = &char_uuid; attr_char_value.p_attr_md = &attr_md; attr_char_value.init_len = 0; attr_char_value.init_offs = 0; attr_char_value.max_len = BLE_GATT_ATT_MTU_DEFAULT; attr_char_value.p_value = 0; return sd_ble_gatts_characteristic_add(p_dfu->service_handle, &char_md, &attr_char_value, &p_dfu->control_point_char); } void ble_dfu_buttonless_on_ctrl_pt_write(ble_gatts_evt_write_t const * p_evt_write) { uint32_t err_code; ble_dfu_buttonless_rsp_code_t rsp_code = DFU_RSP_OPERATION_FAILED; // Start executing the control point write operation /*lint -e415 -e416 -save "Out of bounds access"*/ switch (p_evt_write->data[0]) { case DFU_OP_ENTER_BOOTLOADER: // nrf_gpio_cfg_output(29); // nrf_gpio_pin_set(29); // nrf_delay_ms(2000); err_code = enter_bootloader(); if (err_code == NRF_SUCCESS) { rsp_code = DFU_RSP_SUCCESS; //nrf_gpio_cfg_output(4); //nrf_gpio_pin_set(4); } else if (err_code == NRF_ERROR_BUSY) { rsp_code = DFU_RSP_BUSY; /*nrf_gpio_cfg_output(4); nrf_gpio_pin_set(4);*/ } //break; case DFU_OP_SET_ADV_NAME: if( (p_evt_write->data[1] > NRF_DFU_ADV_NAME_MAX_LENGTH) || (p_evt_write->data[1] == 0)) { // New advertisement name too short or too long. rsp_code = DFU_RSP_ADV_NAME_INVALID; } else { memcpy(m_adv_name.name, &p_evt_write->data[2], p_evt_write->data[1]); m_adv_name.len = p_evt_write->data[1]; err_code = set_adv_name(&m_adv_name); if (err_code == NRF_SUCCESS) { rsp_code = DFU_RSP_SUCCESS; } } break; default: rsp_code = DFU_RSP_OP_CODE_NOT_SUPPORTED; break; } /*lint -restore*/ // Report back in case of error if (rsp_code != DFU_RSP_SUCCESS) { err_code = ble_dfu_buttonless_resp_send((ble_dfu_buttonless_op_code_t)p_evt_write->data[0], rsp_code); if (err_code != NRF_SUCCESS) { mp_dfu->evt_handler(BLE_DFU_EVT_RESPONSE_SEND_ERROR); } // Report the error to the main application mp_dfu->evt_handler(BLE_DFU_EVT_BOOTLOADER_ENTER_FAILED); } } uint32_t ble_dfu_buttonless_bootloader_start_prepare(void) { uint32_t err_code; //nrf_delay_ms(10); // Indicate to main app that DFU mode is starting. mp_dfu->evt_handler(BLE_DFU_EVT_BOOTLOADER_ENTER_PREPARE); err_code = ble_dfu_buttonless_bootloader_start_finalize(); //ResetPinDisable = true; return err_code; } #endif // NRF_DFU_BOTTONLESS_SUPPORT_BOND Fullscreen ble_dfu.c Download /** * Copyright (c) 2017 - 2018, Nordic Semiconductor ASA * * All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, * are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * 2. Redistributions in binary form, except as embedded into a Nordic * Semiconductor ASA integrated circuit in a product or a software update for * such product, must reproduce the above copyright notice, this list of * conditions and the following disclaimer in the documentation and/or other * materials provided with the distribution. * * 3. Neither the name of Nordic Semiconductor ASA nor the names of its * contributors may be used to endorse or promote products derived from this * software without specific prior written permission. * * 4. This software, with or without modification, must only be used with a * Nordic Semiconductor ASA integrated circuit. * * 5. Any software provided in binary form under this license must not be reverse * engineered, decompiled, modified and/or disassembled. * * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ /* Attention! * To maintain compliance with Nordic Semiconductor ASA's Bluetooth profile * qualification listings, this section of source code must not be modified. */ #include "ble_dfu.h" #include #include "ble_hci.h" #include "sdk_macros.h" #include "ble_srv_common.h" #include "nrf_nvic.h" #include "nrf_sdm.h" #include "nrf_soc.h" #include "nrf_log.h" #include "nrf_dfu_ble_svci_bond_sharing.h" #include "nrf_bootloader_info.h" #include "nrf_svci_async_function.h" #include "nrf_pwr_mgmt.h" #include "peer_manager.h" #include "gatts_cache_manager.h" #include "peer_id.h" #include "nrf_gpio.h" #include "nrf_delay.h" #define MAX_CTRL_POINT_RESP_PARAM_LEN 3 /**< Max length of the responses. */ #define BLE_DFU_SERVICE_UUID 0xFE59 /**< The 16-bit UUID of the Secure DFU Service. */ static ble_dfu_buttonless_t m_dfu; /**< Structure holding information about the Buttonless Secure DFU Service. */ //extern bool ResetPinDisable; NRF_SDH_BLE_OBSERVER(m_dfus_obs, BLE_DFU_BLE_OBSERVER_PRIO, ble_dfu_buttonless_on_ble_evt, &m_dfu); /**@brief Function for handling write events to the Buttonless Secure DFU Service Service Control Point characteristic. * * @param[in] p_evt_write Write event received from the BLE stack. */ static void on_ctrlpt_write(ble_gatts_evt_write_t const * p_evt_write) { uint32_t err_code; ble_gatts_rw_authorize_reply_params_t write_authorize_reply; memset(&write_authorize_reply, 0, sizeof(write_authorize_reply)); write_authorize_reply.type = BLE_GATTS_AUTHORIZE_TYPE_WRITE; if (m_dfu.is_ctrlpt_indication_enabled) { write_authorize_reply.params.write.update = 1; write_authorize_reply.params.write.gatt_status = BLE_GATT_STATUS_SUCCESS; } else { write_authorize_reply.params.write.gatt_status = DFU_RSP_CCCD_CONFIG_IMPROPER; } // Authorize the write request do { err_code = sd_ble_gatts_rw_authorize_reply(m_dfu.conn_handle, &write_authorize_reply); } while (err_code == NRF_ERROR_BUSY); if (write_authorize_reply.params.write.gatt_status != BLE_GATT_STATUS_SUCCESS) { return; } // Forward the write event to the Buttonless DFU module. ble_dfu_buttonless_on_ctrl_pt_write(p_evt_write); } /**@brief Write authorization request event handler. * * @details The write authorization request event handler is called when writing to the control point. * * @param[in] p_ble_evt Event received from the BLE stack. */ static void on_rw_authorize_req(ble_evt_t const * p_ble_evt) { if (p_ble_evt->evt.gatts_evt.conn_handle != m_dfu.conn_handle) { return; } const ble_gatts_evt_rw_authorize_request_t * p_auth_req = &p_ble_evt->evt.gatts_evt.params.authorize_request; if ( (p_auth_req->type == BLE_GATTS_AUTHORIZE_TYPE_WRITE) && (p_auth_req->request.write.handle == m_dfu.control_point_char.value_handle) && (p_auth_req->request.write.op != BLE_GATTS_OP_PREP_WRITE_REQ) && (p_auth_req->request.write.op != BLE_GATTS_OP_EXEC_WRITE_REQ_NOW) && (p_auth_req->request.write.op != BLE_GATTS_OP_EXEC_WRITE_REQ_CANCEL) ) { on_ctrlpt_write(&p_auth_req->request.write); } } /**@brief Connect event handler. * * @param[in] p_ble_evt Event received from the BLE stack. */ static void on_connect(ble_evt_t const * p_ble_evt) { m_dfu.conn_handle = p_ble_evt->evt.gap_evt.conn_handle; } /**@brief Disconnect event handler. * * @param[in] p_ble_evt Event received from the BLE stack. */ static void on_disconnect(ble_evt_t const * p_ble_evt) { if (m_dfu.conn_handle != p_ble_evt->evt.gatts_evt.conn_handle) { return; } m_dfu.conn_handle = BLE_CONN_HANDLE_INVALID; } /**@brief Write event handler. * * @param[in] p_ble_evt Event received from the BLE stack. */ static void on_write(ble_evt_t const * p_ble_evt) { const ble_gatts_evt_write_t * p_evt_write = &p_ble_evt->evt.gatts_evt.params.write; // nrf_gpio_cfg_output(29); // nrf_gpio_pin_set(29); // nrf_delay_ms(300); if (p_evt_write->handle != m_dfu.control_point_char.cccd_handle) { return; } if (p_evt_write->len == BLE_CCCD_VALUE_LEN) { // CCCD written, update indications state m_dfu.is_ctrlpt_indication_enabled = ble_srv_is_indication_enabled(p_evt_write->data); NRF_LOG_INFO("Received indication state %d", m_dfu.is_ctrlpt_indication_enabled); } } /**@brief Function for handling the HVC events. * * @details Handles HVC events from the BLE stack. * * @param[in] p_ble_evt Event received from the BLE stack. */ static void on_hvc(ble_evt_t const * p_ble_evt) { uint32_t err_code; ble_gatts_evt_hvc_t const * p_hvc = &p_ble_evt->evt.gatts_evt.params.hvc; // nrf_gpio_cfg_output(29); // nrf_gpio_pin_set(29); // nrf_delay_ms(300); if (p_hvc->handle == m_dfu.control_point_char.value_handle) { // Enter bootloader if we were waiting for reset after hvc indication confimation. if (m_dfu.is_waiting_for_reset) { err_code = ble_dfu_buttonless_bootloader_start_prepare(); if (err_code != NRF_SUCCESS) { m_dfu.evt_handler(BLE_DFU_EVT_BOOTLOADER_ENTER_FAILED); } } } } void ble_dfu_buttonless_on_ble_evt(ble_evt_t const * p_ble_evt, void * p_context) { VERIFY_PARAM_NOT_NULL_VOID(p_ble_evt); switch (p_ble_evt->header.evt_id) { case BLE_GAP_EVT_CONNECTED: on_connect(p_ble_evt); break; case BLE_GAP_EVT_DISCONNECTED: on_disconnect(p_ble_evt); break; case BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST: on_rw_authorize_req(p_ble_evt); break; case BLE_GATTS_EVT_WRITE: on_write(p_ble_evt); break; case BLE_GATTS_EVT_HVC: on_hvc(p_ble_evt); break; default: // no implementation break; } } uint32_t ble_dfu_buttonless_resp_send(ble_dfu_buttonless_op_code_t op_code, ble_dfu_buttonless_rsp_code_t rsp_code) { // Send notification uint32_t err_code; const uint16_t len = 3; uint16_t hvx_len; uint8_t hvx_data[MAX_CTRL_POINT_RESP_PARAM_LEN]; ble_gatts_hvx_params_t hvx_params; memset(&hvx_params, 0, sizeof(hvx_params)); hvx_len = len; hvx_data[0] = DFU_OP_RESPONSE_CODE; hvx_data[1] = (uint8_t)op_code; hvx_data[2] = (uint8_t)rsp_code; hvx_params.handle = m_dfu.control_point_char.value_handle; hvx_params.type = BLE_GATT_HVX_INDICATION; hvx_params.offset = 0; hvx_params.p_len = &hvx_len; hvx_params.p_data = hvx_data; err_code = sd_ble_gatts_hvx(m_dfu.conn_handle, &hvx_params); if ((err_code == NRF_SUCCESS) && (hvx_len != len)) { err_code = NRF_ERROR_DATA_SIZE; } return err_code; } uint32_t ble_dfu_buttonless_bootloader_start_finalize(void) { uint32_t err_code; NRF_LOG_DEBUG("In ble_dfu_buttonless_bootloader_start_finalize "); err_code = sd_power_gpregret_clr(0, 0xffffffff); VERIFY_SUCCESS(err_code); err_code = sd_power_gpregret_set(0, BOOTLOADER_DFU_START); VERIFY_SUCCESS(err_code); // Indicate that the Secure DFU bootloader will be entered m_dfu.evt_handler(BLE_DFU_EVT_BOOTLOADER_ENTER); // nrf_gpio_pin_clear(4); // Signal that DFU mode is to be enter to the power management module nrf_pwr_mgmt_shutdown(NRF_PWR_MGMT_SHUTDOWN_GOTO_DFU); //NVIC_SystemReset(); return NRF_SUCCESS; } uint32_t ble_dfu_buttonless_init(const ble_dfu_buttonless_init_t * p_dfu_init) { uint32_t err_code; ble_uuid_t service_uuid; ble_uuid128_t nordic_base_uuid = BLE_NORDIC_VENDOR_BASE_UUID; VERIFY_PARAM_NOT_NULL(p_dfu_init); // Initialize the service structure. m_dfu.conn_handle = BLE_CONN_HANDLE_INVALID; m_dfu.evt_handler = p_dfu_init->evt_handler; m_dfu.is_waiting_for_reset = false; m_dfu.is_ctrlpt_indication_enabled = false; err_code = ble_dfu_buttonless_backend_init(&m_dfu); VERIFY_SUCCESS(err_code); BLE_UUID_BLE_ASSIGN(service_uuid, BLE_DFU_SERVICE_UUID); // Add the DFU service declaration. err_code = sd_ble_gatts_service_add(BLE_GATTS_SRVC_TYPE_PRIMARY, &service_uuid, &(m_dfu.service_handle)); VERIFY_SUCCESS(err_code); // Add vendor specific base UUID to use with the Buttonless DFU characteristic. err_code = sd_ble_uuid_vs_add(&nordic_base_uuid, &m_dfu.uuid_type); VERIFY_SUCCESS(err_code); // Add the Buttonless DFU Characteristic (with bonds/without bonds). err_code = ble_dfu_buttonless_char_add(&m_dfu); VERIFY_SUCCESS(err_code); return NRF_SUCCESS; } Yes I am using custom board. I am attaching ble_dfu.c and ble_dfu_unbounded.c files of my application code. i have not make any changed in both files. One more thing , What is the need of making reset pin low during jumping from application to bootloader?

Problem in jumping from application to bootloader

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