diff --git a/lib/liblynq-sim/include/lynq_sim.h b/lib/liblynq-sim/include/lynq_sim.h
index 35d67db..846a1ec 100755
--- a/lib/liblynq-sim/include/lynq_sim.h
+++ b/lib/liblynq-sim/include/lynq_sim.h
@@ -5,7 +5,7 @@
 #     Version: V1.0
 #     LastChange: 2020-07-29 
 #     History: 
-# If you need to use any API under lynq_sim, you must first call the init_sim() function to initialize these functions.
+# If you need to use any API under lynq_sim, you must first call the lynq_sim_init() function to initialize these functions.
 =============================================================================*/
 #ifndef __LYNQ_SIM__
 #define __LYNQ_SIM__
@@ -15,8 +15,6 @@
 
 int lynq_get_sim_status(int *card_status);
 int lynq_get_imsi(char buf[]);
-
-/*add by lei*/
 int lynq_sim_init(int utoken);
 int lynq_sim_deinit(void);
 int lynq_enable_pin(char pin[]);
@@ -30,7 +28,28 @@
 int lynq_switch_card(int slot);
 int lynq_screen(int num);
 int lynq_get_imei(char buf[]);
-/*add by lei*/
+
+/**
+ * @brief                   Request SIM I/O operation.
+ *                          This is similar to the TS 27.007 "restricted SIM" operation
+ *                          where it assumes all of the EF selection will be done by the callee.
+ * @param  list             type: [IN] list[0]:one of the commands listed for TS 27.007 +CRSM.(command)
+ *                          type: [IN] list[1]:EF id(fileid)
+ *                          type: [IN] list[2]:offset(p1)
+ *                          type: [IN] list[3]:offset(p2)
+ *                          type: [IN] list[4]:response len,sometimes needn't care(p3)
+ * @param  path             type: [IN] "pathid" from TS 27.007 +CRSM command.
+                            type: [IN] Path is in hex asciii format eg "7f205f70"
+                            type: [IN] Path must always be provided.
+ * @param  data             type: [IN] May be NULL
+ * @param  pin2             type: [IN] May be NULL
+ * @param  aidPtr           type: [IN] AID value, See ETSI 102.221 8.1 and 101.220 4, NULL if no value.
+ * @param  sw               type: [OUT] 
+ * @param  simResponse      type: [OUT] response
+ * @return int
+ */
+int lynq_req_sim_io(int list[5], char *path, char *data, char *pin2, char *aidPtr, int sw[2], char *simResponse);
+
 
 
 #ifdef __cplusplus