OTA升级从user2.bin ota升级到user1.bin失败。

[Xuedong]

使用NONOS SDK 2.0从从user1.bin ota升级到user2.bin成功，反过来就会失败，下面是log：

system_upgrade_start
upgrade_connect 37224
[OTA]Upgrading...
upgrade_connect_cb
pusrdata = HTTP/1.1 200 OK
Date: Sun, 19 Mar 2017 02:21:19 GMT
Server: Apache/2.4.23 (Win32) PHP/5.6.25
Last-Modified: Sun, 19 Mar 2017 01:37:15 GMT
ETag: "4c284-54b0b73556adc"
Accept-Ranges: bytes
Content-Length: 311940
Connection: close
Content-Type: application/octet-stream


sumlength = 311940
sec_block 77
.............................................................................upgrade_get_sum_disconcb 34576
棋衷?殊屒!嘍\0?屾? ?(H圽0?鴮!O?1?▎??!
J?!!L!?!?
11?▎
!!!
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!!!
JP9?L!8?!嗈1!O??!!啴!!L?J?!哊!?!O?1?▎!? 殔?L!??嗈1??O?? B9?L!J?!嗈1E?!O??!!啴!!?
J?!?
!?!On11?▎?!!
Jち?L!?)!嗈1??O?? !啴!!L!袹?!嗈1?!O?E!!啴!!!
J?!?
!?!O
请帮忙分析一下是什么原因，谢谢！

[ESP_Faye]

启动时的 log 是怎样的？会不会其实并没有跳到 user2 运行，还在运行 user1.bin 又擦掉了 user1 呢？