diff -r 76e8ec46828a -r cde2e410b874 modbus/mb_runtime.c
--- a/modbus/mb_runtime.c	Fri Dec 25 17:12:02 2020 +0000
+++ b/modbus/mb_runtime.c	Thu Jan 28 14:51:16 2021 +0000
@@ -200,12 +200,42 @@
 }
 
 
-static int __read_inbits   (void *mem_map, u16 start_addr, u16 bit_count, u8  *data_bytes)
-  {return   __pack_bits(((server_mem_t *)mem_map)->ro_bits, start_addr, bit_count, data_bytes);}
-static int __read_outbits  (void *mem_map, u16 start_addr, u16 bit_count, u8  *data_bytes)
-  {return   __pack_bits(((server_mem_t *)mem_map)->rw_bits, start_addr, bit_count, data_bytes);}
-static int __write_outbits (void *mem_map, u16 start_addr, u16 bit_count, u8  *data_bytes)
-  {return __unpack_bits(((server_mem_t *)mem_map)->rw_bits, start_addr, bit_count, data_bytes); }
+static int __read_inbits   (void *mem_map, u16 start_addr, u16 bit_count, u8  *data_bytes) {
+  int res = __pack_bits(((server_mem_t *)mem_map)->ro_bits, start_addr, bit_count, data_bytes);
+  
+  if (res >= 0) {
+    /* update the flag and counter of Modbus requests we have processed. */
+    ((server_mem_t *)mem_map)->flag_read_req_counter++;
+    ((server_mem_t *)mem_map)->flag_read_req_flag = 1;
+  }
+
+  return res;
+}
+
+static int __read_outbits  (void *mem_map, u16 start_addr, u16 bit_count, u8  *data_bytes) {
+  int res = __pack_bits(((server_mem_t *)mem_map)->rw_bits, start_addr, bit_count, data_bytes);
+  
+  if (res >= 0) {
+    /* update the flag and counter of Modbus requests we have processed. */
+    ((server_mem_t *)mem_map)->flag_read_req_counter++;
+    ((server_mem_t *)mem_map)->flag_read_req_flag = 1;
+  }
+
+  return res;
+}
+
+static int __write_outbits (void *mem_map, u16 start_addr, u16 bit_count, u8  *data_bytes) {
+  int res = __unpack_bits(((server_mem_t *)mem_map)->rw_bits, start_addr, bit_count, data_bytes);
+  
+  if (res >= 0) {
+    /* update the flag and counter of Modbus requests we have processed. */
+    ((server_mem_t *)mem_map)->flag_write_req_counter++;
+    ((server_mem_t *)mem_map)->flag_write_req_flag = 1;
+  }
+
+  return res;
+}
+
 
 
 
@@ -214,6 +244,10 @@
   if ((start_addr + word_count) > MEM_AREA_SIZE)
     return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */
 
+  /* update the flag and counter of Modbus requests we have processed. */
+  ((server_mem_t *)mem_map)->flag_read_req_counter++;
+  ((server_mem_t *)mem_map)->flag_read_req_flag = 1;
+
   /* use memcpy() because loop with pointers (u16 *) caused alignment problems */
   memcpy(/* dest */ (void *)data_words,
          /* src  */ (void *)&(((server_mem_t *)mem_map)->ro_words[start_addr]),
@@ -228,6 +262,10 @@
   if ((start_addr + word_count) > MEM_AREA_SIZE)
     return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */
 
+  /* update the flag and counter of Modbus requests we have processed. */
+  ((server_mem_t *)mem_map)->flag_read_req_counter++;
+  ((server_mem_t *)mem_map)->flag_read_req_flag = 1;
+
   /* use memcpy() because loop with pointers (u16 *) caused alignment problems */
   memcpy(/* dest */ (void *)data_words,
          /* src  */ (void *)&(((server_mem_t *)mem_map)->rw_words[start_addr]),
@@ -243,6 +281,10 @@
   if ((start_addr + word_count) > MEM_AREA_SIZE)
     return -ERR_ILLEGAL_DATA_ADDRESS; /* ERR_ILLEGAL_DATA_ADDRESS defined in mb_util.h */
 
+  /* update the flag and counter of Modbus requests we have processed. */
+  ((server_mem_t *)mem_map)->flag_write_req_counter++;
+  ((server_mem_t *)mem_map)->flag_write_req_flag = 1;
+
   /* WARNING: The data returned in the data_words[] array is not guaranteed to be 16 bit aligned.
    *           It is not therefore safe to cast it to an u16 data type.
    *           The following code cannot be used. memcpy() is used instead.
@@ -545,6 +587,10 @@
 		//   -1  -->    modbus node created!; no thread  created
 		//  >=0  -->    modbus node created!;    thread  created!
 		server_nodes[index].mb_nd = -2; 
+		server_nodes[index].mem_area.flag_write_req_flag    = 0; 
+		server_nodes[index].mem_area.flag_write_req_counter = 0; 
+		server_nodes[index].mem_area.flag_read_req_counter  = 0; 
+		server_nodes[index].mem_area.flag_read_req_flag     = 0; 
         /* see comment in mb_runtime.h to understad why we need to initialize these entries */
         switch (server_nodes[index].node_address.naf) {
             case naf_tcp: