diff --git a/modbus/mb_controller/serial/mbc_serial_master.c b/modbus/mb_controller/serial/mbc_serial_master.c
index bee0afa..674854c 100644
--- a/modbus/mb_controller/serial/mbc_serial_master.c
+++ b/modbus/mb_controller/serial/mbc_serial_master.c
@@ -693,11 +693,23 @@ esp_err_t mbc_serial_master_create(mb_communication_info_t *config, void **ctx)
 
     if (pcomm_info->mode == MB_RTU)
     {
+#if ( CONFIG_FMB_COMM_MODE_RTU_EN )
         err = mbm_rtu_create(pcomm_info, &pinst);
+#else
+        ESP_LOGE(TAG, "RTU mode is not enabled in the configuration.");
+        ret = ESP_ERR_NOT_SUPPORTED;
+        goto error;
+#endif // CONFIG_FMB_COMM_MODE_RTU_EN
     }
     else if (pcomm_info->mode == MB_ASCII)
     {
+#if ( CONFIG_FMB_COMM_MODE_ASCII_EN )
         err = mbm_ascii_create(pcomm_info, &pinst);
+#else
+        ESP_LOGE(TAG, "ASCII mode is not enabled in the configuration.");
+        ret = ESP_ERR_NOT_SUPPORTED;
+        goto error;
+#endif // CONFIG_FMB_COMM_MODE_ASCII_EN
     }
     MB_GOTO_ON_FALSE((err == MB_ENOERR), ESP_ERR_INVALID_STATE, error, TAG,
                      "mb object create returns (0x%x).", (int)err);
diff --git a/modbus/mb_controller/serial/mbc_serial_slave.c b/modbus/mb_controller/serial/mbc_serial_slave.c
index 6e317b2..81d40a2 100644
--- a/modbus/mb_controller/serial/mbc_serial_slave.c
+++ b/modbus/mb_controller/serial/mbc_serial_slave.c
@@ -255,11 +255,23 @@ esp_err_t mbc_serial_slave_create(mb_communication_info_t *config, void **ctx)
     // Initialize Modbus stack using mbcontroller parameters
     if (pcomm_info->mode == MB_RTU)
     {
+#if (CONFIG_FMB_COMM_MODE_RTU_EN)
         err = mbs_rtu_create(pcomm_info, &pinst);
+#else
+        ESP_LOGE(TAG, "RTU mode is not enabled in the configuration.");
+        ret = ESP_ERR_NOT_SUPPORTED;
+        goto error;
+#endif
     }
     else if (pcomm_info->mode == MB_ASCII)
     {
+#if (CONFIG_FMB_COMM_MODE_ASCII_EN)
         err = mbs_ascii_create(pcomm_info, &pinst);
+#else
+        ESP_LOGE(TAG, "ASCII mode is not enabled in the configuration.");
+        ret = ESP_ERR_NOT_SUPPORTED;
+        goto error;
+#endif // CONFIG_FMB_COMM_MODE_ASCII_EN
     }
     MB_GOTO_ON_FALSE((err == MB_ENOERR), ESP_ERR_INVALID_STATE, error, TAG,
                      "mbs create returns (0x%x).", (int)err);
@@ -290,4 +302,4 @@ error:
     return ret;
 }
 
-#endif
\ No newline at end of file
+#endif // #if (CONFIG_FMB_COMM_MODE_ASCII_EN || CONFIG_FMB_COMM_MODE_RTU_EN)
\ No newline at end of file
diff --git a/modbus/mb_objects/mb_master.c b/modbus/mb_objects/mb_master.c
index c813a2d..b5785b9 100644
--- a/modbus/mb_objects/mb_master.c
+++ b/modbus/mb_objects/mb_master.c
@@ -82,10 +82,10 @@ static void mbm_set_dest_addr(mb_base_t *inst, uint8_t dest_addr);
 static uint8_t mbm_get_dest_addr(mb_base_t *inst);
 static void mbm_get_pdu_send_buf(mb_base_t *inst, uint8_t **pbuf);
 
-#if (MB_MASTER_ASCII_ENABLED || MB_MASTER_RTU_ENABLED) 
-
 typedef struct _port_serial_opts mb_serial_opts_t;
 
+#if (MB_MASTER_RTU_ENABLED)
+
 mb_err_enum_t mbm_rtu_create(mb_serial_opts_t *ser_opts, void **in_out_obj)
 {
     MB_RETURN_ON_FALSE((ser_opts && in_out_obj), MB_EINVAL, TAG, "invalid options for the instance.");
@@ -139,6 +139,10 @@ error:
     return ret;
 }
 
+#endif /* MB_MASTER_RTU_ENABLED */
+
+#if (MB_MASTER_ASCII_ENABLED)
+
 mb_err_enum_t mbm_ascii_create(mb_serial_opts_t *ser_opts, void **in_out_obj)
 {
     MB_RETURN_ON_FALSE((ser_opts && in_out_obj), MB_EINVAL, TAG, "invalid options for the instance.");
@@ -192,7 +196,7 @@ error:
     return ret;
 }
 
-#endif
+#endif /* MB_MASTER_ASCII_ENABLED */
 
 #if (CONFIG_FMB_COMM_MODE_TCP_EN)
 
diff --git a/modbus/mb_objects/mb_slave.c b/modbus/mb_objects/mb_slave.c
index 40b09da..56d3af3 100644
--- a/modbus/mb_objects/mb_slave.c
+++ b/modbus/mb_objects/mb_slave.c
@@ -3,6 +3,7 @@
  *
  * SPDX-License-Identifier: Apache-2.0
  */
+#include "mb_config.h"
 #include "mb_common.h"
 #include "mb_proto.h"
 #include "mb_func.h"
@@ -15,6 +16,8 @@
 
 static const char *TAG = "mb_object.slave";
 
+#if (MB_SLAVE_ASCII_ENABLED || MB_SLAVE_RTU_ENABLED || MB_TCP_ENABLED)
+
 static mb_fn_handler_t slave_handlers[MB_FUNC_HANDLERS_MAX] =
     {
 #if MB_FUNC_OTHER_REP_SLAVEID_ENABLED
@@ -73,10 +76,10 @@ mb_err_enum_t mbs_disable(mb_base_t *inst);
 mb_err_enum_t mbs_poll(mb_base_t *inst);
 mb_err_enum_t mbs_set_slv_id(mb_base_t *inst, uint8_t slv_id, bool is_running, uint8_t const *slv_idstr, uint16_t slv_idstr_len);
 
-#if (CONFIG_FMB_COMM_MODE_ASCII_EN || CONFIG_FMB_COMM_MODE_RTU_EN)
-
 typedef struct _port_serial_opts mb_serial_opts_t;
 
+#if (MB_SLAVE_RTU_ENABLED)
+
 mb_err_enum_t mbs_rtu_create(mb_serial_opts_t *ser_opts, void **in_out_obj)
 {
     mb_err_enum_t ret = MB_ENOERR;
@@ -124,6 +127,10 @@ error:
     return ret;
 }
 
+#endif /* MB_SLAVE_RTU_ENABLED */
+
+#if (MB_SLAVE_ASCII_ENABLED)
+
 mb_err_enum_t mbs_ascii_create(mb_serial_opts_t *ser_opts, void **in_out_obj)
 {
     mb_err_enum_t ret = MB_ENOERR;
@@ -170,9 +177,9 @@ error:
     return ret;
 }
 
-#endif
+#endif /* MB_SLAVE_ASCII_ENABLED */
 
-#if (CONFIG_FMB_COMM_MODE_TCP_EN)
+#if (MB_TCP_ENABLED)
 
 mb_err_enum_t mbs_tcp_create(mb_tcp_opts_t *tcp_opts, void **in_out_obj)
 {
@@ -381,3 +388,5 @@ mb_err_enum_t mbs_poll(mb_base_t *inst)
     }
     return status;
 }
+
+#endif /* (MB_SLAVE_ASCII_ENABLED || MB_SLAVE_RTU_ENABLED || MB_TCP_ENABLED) */
\ No newline at end of file