diff --git a/TC1/http_server/app_httpd.c b/TC1/http_server/app_httpd.c
index 32453e2..b0a8115 100644
--- a/TC1/http_server/app_httpd.c
+++ b/TC1/http_server/app_httpd.c
@@ -46,7 +46,7 @@
 static bool is_http_init;
 static bool is_handlers_registered;
 struct httpd_wsgi_call g_app_handlers[];
-char power_info_json[1130] = { 0 };
+char power_info_json[1140] = { 0 };
 
 static int HttpGetIndexPage(httpd_request_t *req)
 {
@@ -99,9 +99,16 @@ exit:
 
 static int HttpGetPowerInfo(httpd_request_t *req)
 {
-    char* powers = GetPowerRecord();
-    sprintf(power_info_json, POWER_INFO_JSON, power_record.idx, powers);
     OSStatus err = kNoErr;
+    char buf[4];
+    err = httpd_get_data(req, buf, 4);
+    require_noerr(err, exit);
+
+    int idx = 0;
+    sscanf(buf, "%d", &idx);
+
+    char* powers = GetPowerRecord(idx);
+    sprintf(power_info_json, POWER_INFO_JSON, power_record.idx, PW_NUM, powers);
     send_http(power_info_json, strlen(power_info_json), exit, &err);
 exit:
     return err;
@@ -172,7 +179,7 @@ struct httpd_wsgi_call g_app_handlers[] = {
     {"/", HTTPD_HDR_DEFORT, 0, HttpGetIndexPage, NULL, NULL, NULL},
     {"/socket", HTTPD_HDR_DEFORT, 0, NULL, HttpSetSocketStatus, NULL, NULL},
     {"/status", HTTPD_HDR_DEFORT, 0, HttpGetTc1Status, NULL, NULL, NULL},
-    {"/power", HTTPD_HDR_DEFORT, 0, HttpGetPowerInfo, NULL, NULL, NULL},
+    {"/power", HTTPD_HDR_DEFORT, 0, NULL, HttpGetPowerInfo, NULL, NULL},
     {"/wifi/config", HTTPD_HDR_DEFORT, 0, HttpGetWifiConfig, HttpSetWifiConfig, NULL, NULL},
     {"/wifi/scan", HTTPD_HDR_DEFORT, 0, HttpGetWifiScan, HttpSetWifiScan, NULL, NULL},
 };
diff --git a/TC1/http_server/app_httpd.h b/TC1/http_server/app_httpd.h
index b45494f..798e2cb 100644
--- a/TC1/http_server/app_httpd.h
+++ b/TC1/http_server/app_httpd.h
@@ -56,7 +56,7 @@
     'gateway':'%s'\
 }"
 
-#define POWER_INFO_JSON "{'idx':%d, 'powers:[%s]'}"
+#define POWER_INFO_JSON "{'idx':%d,'len':%d,'powers:[%s]'}"
 
 int AppHttpdStart(void);
 int AppHttpdStop();
diff --git a/TC1/http_server/index.html b/TC1/http_server/index.html
index 2caa689..62e3d5c 100644
--- a/TC1/http_server/index.html
+++ b/TC1/http_server/index.html
@@ -251,16 +251,21 @@ HttpGet("/status", function (re) {
     }
 });
 
+var first_load_power = true;
+var power_idx = 1;
+var position = 10;
 function GetPowerRecord() {
-    HttpGet("/power", function (re) {
-    var power = JSON.parse(re);
-    var html = "";
-    for (var i = 0; i < power.powers.length; i++) {
-        html += "<div class='power_pre' style='height:"+power.powers[i]+"px;left:"+((i+1)*10)+"px;'></div>";
-        power_line.innerHTML = html;
+    HttpPost("/power", function (re) {
+        var power = JSON.parse(re);
+        power_idx = power.idx + 1;
+        var html = "";
+        for (var i = 0; i <= power.idx; i++) {
+            html += "<div class='power_pre' style='height:"+power.powers[i]+"px;left:"+position+"px;'></div>";
+            position += 10;
+        }
+        power_line.innerHTML += html;
         //滑动到最后
-    }
-});
+    }, idx.toString());
 }
 
 function SetOK(i) {
diff --git a/TC1/user_power.c b/TC1/user_power.c
index 3456c64..1d5d815 100644
--- a/TC1/user_power.c
+++ b/TC1/user_power.c
@@ -10,7 +10,7 @@
 
 mico_timer_t power_timer;
 
-PowerRecord power_record = { 0, { 50,55,60,65,70,75,80,85,90,95,90,85,80,75,70,65,60,65,70,75,80,85,90,95,90,85,80,75,70,65,60,65,70,75,80,85,90,95,90,85,80,75,70,65,60 } };
+PowerRecord power_record = { 44, { 50,55,60,65,70,75,80,85,90,95,90,85,80,75,70,65,60,65,70,75,80,85,90,95,90,85,80,75,70,65,60,65,70,75,80,85,90,95,90,85,80,75,70,65,60 } };
 
 static uint32_t clock_count_last = 0;
 static uint32_t clock_count = 0;
@@ -21,20 +21,18 @@ char power_record_str[1101] = { 0 };
 
 void SetPowerRecord(PowerRecord* pr, uint32_t pw)
 {
-    if (pr->idx >= PW_NUM)
-    {
-        pr->idx = 0;
-    }
-    pr->powers[pr->idx++] = pw;
+    pr->powers[(++pr->idx)% PW_NUM] = pw;
 }
 
-char* GetPowerRecord()
+char* GetPowerRecord(int idx)
 {
-    int i = 0;
+    if (idx > power_record.idx) return NULL;
+
+    int i = idx > 0 ? idx : (power_record.idx - PW_NUM - 1);
     char* tmp = power_record_str;
-    for (; i < PW_NUM; i++)
+    for (; i <= power_record.idx; i++)
     {
-        sprintf(tmp, "%d,", power_record.powers[i]);
+        sprintf(tmp, "%d,", power_record.powers[i%PW_NUM]);
         tmp += strlen(tmp);
     }
     *(--tmp) = 0;
diff --git a/TC1/user_power.h b/TC1/user_power.h
index 6be3209..af9c888 100644
--- a/TC1/user_power.h
+++ b/TC1/user_power.h
@@ -10,7 +10,7 @@ typedef struct
 
 extern PowerRecord power_record;
 
-char* GetPowerRecord();
+char* GetPowerRecord(int idx);
 void PowerInit(void);
 void SetPowerRecord(PowerRecord* pr, uint32_t pw);