donesvarc
Czech Republic
Asked
— Edited
Resolved by DJ Sures!
What I am doing wrong:
I connected wifi module USR-WIFI232T with adopted power from 5v to 3.3v. Tx from EZB(v.3) connected to Rx on wifi module and Rx on EZB to Tx on Wifi module.
I connected my PC with Wifi module and open IE for configuration. The setting is here:
and setting of AP is here:
I changed serial Baud rate from 115200 to 9600 and rest parameters left without changes as they are.
I wrote IP address and Port ID to EZBuilder:
and tried to connect to EZBoard. For approximately 10s blue LED stopped flashing and stayed shine, but after this moment LED started flashing again and EZBuilder wrote Disconnected:
Specification of Wifi module is here:
USR-WIFI232-T.pdf
Secondly, I'm not sure what you meant by adopting power from 5V to 3.3V. Is that for VCC of the entire EZ-B or just for the WiFi module?
Remember that if the EZ-B v3 is being powered at 5V then the logic signals will be at 5V and when interfacing to a 3.3V device you may need a voltage divider or logic level shifter to avoid damage if the pins aren't 5V tolerant.
What didn't happen is the EZ-B v3 responding with the connection response.
This could be due to the Wi-Fi module RX not connected correctly to the EZ-B v3. Or, as jeremie stated, the Wi-Fi module is not 5v tolerant on I/O. This would cause the RX pin of the Wi-Fi module to be damaged.
The difference between 5v and 3.3v is significant with a ~35% difference.
If the Wi-Fi module is not damaged, you may recover by using a simple resistor based level shifter. This is a creative way to do it: http://jamesreubenknowles.com/level-shifting-stragety-experments-1741
*Remember, you only need to shift the level in one directly (RX on the Wi-Fi). This is because the EZ-B v3 has no problem receiving a 3.3v signal on the TX from the Wi-Fi. The issue is when the EZ-B v3 outputs 5v on it's TX to the RX of the Wi-Fi. Only the RX on the Wi-Fi needs to be level shifted to 3.3v fro 5v.