diff --git a/src/main/java/com/telpo/dipperposition/service/impl/DipperAstPosAsyncTaskServiceImpl.java b/src/main/java/com/telpo/dipperposition/service/impl/DipperAstPosAsyncTaskServiceImpl.java
index 5417f94..2685cc2 100644
--- a/src/main/java/com/telpo/dipperposition/service/impl/DipperAstPosAsyncTaskServiceImpl.java
+++ b/src/main/java/com/telpo/dipperposition/service/impl/DipperAstPosAsyncTaskServiceImpl.java
@@ -217,6 +217,16 @@ public class DipperAstPosAsyncTaskServiceImpl implements IDipperAstPosAsyncTaskS
         astPosCmd += "70170000";
         astPosCmd += "A0860100";
 
+        log.info(astPosCmd);
+        String checkSum = HexConvert.makeChecksum(astPosCmd).toUpperCase();
+        StringBuffer astCheckSumBuf = new StringBuffer();
+        astCheckSumBuf.append(checkSum);
+        while (astCheckSumBuf.length()<4) {
+            astCheckSumBuf.insert(0,"0");
+        }
+        checkSum = astCheckSumBuf.toString();
+        log.info(checkSum);
+
         byte[] astPosCmdBytes = HexConvert.hexStringToBytes(astPosCmd);
         StringBuffer astPosCmdBuf = new StringBuffer();
         for(int i=0; i<astPosCmdBytes.length; i++) {
@@ -227,7 +237,6 @@ public class DipperAstPosAsyncTaskServiceImpl implements IDipperAstPosAsyncTaskS
             astPosCmdBuf.append(s + " ");
         }
 
-        String checkSum = HexConvert.makeChecksum(astPosCmd).toUpperCase();
         return astPosCmdBuf.toString() + checkSum.substring(0,1) + " " + checkSum.substring(2,3);
 
     }
diff --git a/src/main/java/com/telpo/dipperposition/service/impl/DipperAstTimeAsyncTaskServiceImpl.java b/src/main/java/com/telpo/dipperposition/service/impl/DipperAstTimeAsyncTaskServiceImpl.java
index f5af6a0..788bee6 100644
--- a/src/main/java/com/telpo/dipperposition/service/impl/DipperAstTimeAsyncTaskServiceImpl.java
+++ b/src/main/java/com/telpo/dipperposition/service/impl/DipperAstTimeAsyncTaskServiceImpl.java
@@ -94,7 +94,16 @@ public class DipperAstTimeAsyncTaskServiceImpl implements IDipperAstTimeAsyncTas
             astTimeCmdBuf.append(s + " ");
         }
 
+        log.info(astTimeCmd);
         String checkSum = HexConvert.makeChecksum(astTimeCmd).toUpperCase();
+        StringBuffer astCheckSumBuf = new StringBuffer();
+        astCheckSumBuf.append(checkSum);
+        while (astCheckSumBuf.length()<4) {
+            astCheckSumBuf.insert(0,"0");
+        }
+        checkSum = astCheckSumBuf.toString();
+        log.info(checkSum);
+
         return astTimeCmdBuf.toString() + checkSum.substring(0,1) + " " + checkSum.substring(2,3);
         //String hexIn = astTimeCmd + HexConvert.makeChecksum(astTimeCmd);
         //log.info("DipperAstTimeAsyncTaskServiceImpl 返回时间：" + hexIn);