I just bought 3 pcs of ESP-01 together with USB to serial adapter. Testing it using the default firmware resulted in as follows:
1. Displays a few garbled characters then "ready" but inputting AT command does not result to anything, just the prompt returning to first column.
2. I tried flashing nodemcu_latest.bin dated 8/31/2015 and while it displays "lua: cannot open init.lua" it accepts entries and responds. However, what I need is the AT command as I just need the Esp-01 to send serial data via WiFi.
3. Then flashing it with AT22SDK100-2015-03-20-boot1.2.bin and *.3b.bin resulted in "MEM Check Fail !!!"
So I assume a have a good ESP-01s except that I have the wrong AT firmware to drive it.
Will appreciate any help pointing me to the right direction,
Vic