stuck in  Uploading stub...

```
Command: esptool.py --port COM6 --baud 115200 --after no_reset write_flash --flash_mode dio 0x00000 C:\Users\pussycat\Downloads\AIThinker_ESP8266_8Mbit_v1.5.4.1.bin

esptool.py v2.6
Serial port COM6
Connecting....
Detecting chip type... ESP8266
Chip is ESP8266EX
Features: WiFi
MAC: 40:f5:20:32:f7:7b
Uploading stub...
```