Questions about using ESP8266_NONOS_SDK_V1.5.4_16_05_20， no uart print after initialization

[blacksea3]

I just use ESP8266IDE to compile ESP8266_NONOS_SDK_V1.5.4_16_05_20, using IoT_Demo in examples. Compile OK.
Then I download bins as following:
eagle.flash.bin-------->0x00000
eagle.irom0text.bin---->0x40000
esp_init_data_default.bin--->0x7C000
blank.bin--->0x7E000

But When I power up. esp8266 just put some chars with 74880 baud rate. Then nothing happen. Clearly it should alse print sth like "SDK version:xxx because I use os_printf in user_init() ?
Why?
thanks! Email: 774832389@qq.com.

我用ESP8266IDE编译了ESP8266_NONOS_SDK_V1.5.4_16_05_20，app文件夹放了Iot_Demo,编译成功
按如下的顺序下载bin:
eagle.flash.bin-------->0x00000
eagle.irom0text.bin---->0x40000
esp_init_data_default.bin--->0x7C000
blank.bin--->0x7E000
但是上电后，esp8266仅仅发送了ROM固化的启动信息（74880的波特率），然后什么都不发了，可是我看到user_init()里面写了os_printf()等串口发送程序，请问是问什么？
非常感谢回答！ 邮箱774832389@qq.com.

[pratik]

Are you getting no output at all from the serial terminals?
Please make sure Rx and Tx pins are not reversed. Also, make sure your module is getting reliable power. Also, make sure that the boot mode is set to flash execution when power is turned on!
Because if you are able to program the module, means your chipset is OK. Seems like some other issue. Probably just your serial terminal issue?

[XIAOZ]

我也遇到同样的问题，使用IOT_DEMO，只有启动信息 使用iot espressif（app）连接不上设备端