1. 0x00 地址读取错误.
ets Jan  8 2013,rst cause:1, boot mode:(3,2)  
ets_main.c  

2.spi 模式错误( use quad mode for dual flash)

ets Jan  8 2013,rst cause:1, boot mode:(3,2)  
load 0x40100000, len 612, room 16  
tail 4  
chksum 0xef  
load 0x88888888, len -2004318072, room 4  
flash read err, ets_unpack_flash_code  
ets_main.c  

3.boot load jump error.(user.bin not correct)

ets Jan  8 2013,rst cause:1, boot mode:(3,2)  
load 0x40100000, len 612, room 16  
tail 4  
chksum 0x12  
load 0x3ffe8000, len 788, room 4  
tail 0  
chksum 0x50  
load 0x3ffe8314, len 264, room 8  
tail 0  
chksum 0x4a  
csum 0x4a  
2nd boot version : 1.1  
SPI Speed      : 40MHz  
SPI Mode       : DIO  
SPI Flash Size : 4Mbit  
jump to run user1  
user code done  

4.dual flash(boot+user.bin mode) ==>use download tool version v0.9.3.1 and above 刷写工具版本错误

ets Jan  8 2013,rst cause:1, boot mode:(3,3)  
load 0x40100000, len 612, room 16  
tail 4  
chksum 0x12  
load 0x3ffe8000, len 788, room 4  
tail 0  
chksum 0x50  
load 0x3ffe8314, len 264, room 8  
tail 0  
chksum 0x4a  
csum 0x4a  
2nd boot version : 1.1  
SPI Speed      : 40MHz  
SPI Mode       :   SPI Flash Size : 4Mbit  
jump to run user1  
Fatal exception (28):  
epc1=0x401001a4, epc2=0x00000000, epc3=0x00000000, excvaddr=0x0000009c, depc=0x00000000  
Fatal exception (28):  
epc1=0x401001a4, epc2=0x00000000, epc3=0x00000000, excvaddr=0x0000009c, depc=0x00000000  
Fatal exception (28):  
epc1=0x401001a4, epc2=0x00000000, epc3=0x00000000, excvaddr=0x0000009c, depc=0x00000000