Asked — Edited

What Is The Pinout On Bluetooth Connection

i just got my WIFI board in and kinda lazy to check it i know its 3.3 volts ,gnd tx and rx


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i guess i found it when i removed the board ,small letters near the connector


board i have you can barly see it,the bluetooth hides it and the 40 pin sockets covers part of it


It attempting to use the wifi board that is recommended, it draws 300 ma and the EZ-B will go into brownout. Using separate power and a 3.3v regulator is a better option.


yes i saw that,everything on EZB you mostly need a seperate power supply i use 3.3 volt LDO,as for all my power supply designs,all most every battery design uses LDO


@robotMaker, that is untrue. It depends what version you have. The two most recent versions use a 3 amp VR for the Microchip and Bluetooth - the wifi adapter only drawing 200mha wont' affect it at all :)

Also, the only time you need to use separate power is when you exceed the 5 amps on the I/o lines. The I/o is powered by 5 amps, and you can use a simple calculator to figure out how much you're drawing. With a fan, I successfully pull 7-8 amps from my power source.


Thanks DJ ,i just thought from what ROBOT-DOC said that i needed a seperate power supply I do know that WIFI board takes 300ma and thought from what he said that the board has less then 300 ma

i think mostly only SERVO'S need a seperate power supply,i have all my 9 of them version 3


I don't know what other reason causes the Blue flashing LED on the EZ-B to go out when I attempt to power the WiFi chip from the bluetooth connector. When the WiFi is powered from another source the EZ-B Blue LED continues to flash. Of course even though my ASUS router recognizes the WiFi board and the IP address discovered performing the set-up steps there is still no correct communication between the ARC app and the EZ-B. (Tx to Rx and Rx to Tx) results in an error condition that the EZ-B has Version 8.5 and needs to be flashed.


What version is your EZB it will say it after the big letters of EZ-B on the PCB


The board I purchased has the silk screen letters EZ-B V3


Same as mine ,i think its the lastest version,this week will try the board and see if i get the same results.

I do see something,on back of the board there is 2 pads one 5 volts and one 3.3 volts 5 volt pad is jumped,so maybe the bluetooth is set at 5 volts. THAT may be the problem ?

I can check it tonight to see if its 5 volts going to bluetooth board,if you have a meter handy check the voltage at the connector ,if its 5 volts ,cut the trace between the 2 pads of 5 volts and jump the 2 pads on the 3.3 volts,.make shore you check the pads with a meter after you cut them from looking at the board it looks like thats only for bluetooth connection or WIFI

Second i am working on the WIFI board to have both WIRED and WIFI since it has PH I/O needed for wired networking


There is no firmware 8.5... That means you are connecting to an internal modem of your computer.

@RobotMaker, you can tell what version of the PCB you have here:

If the WIFI is connected correctly, there is no reason it should brown out the PCB. Unless the connections are shorted, or the wifi module is drawing more than 3 amps



DJ what are the connections pads on the back of the EZB for ,one says 5 volts that shows a short and the other shows 3.3 volts that is open ,it next to the bluetooth connector v+ pin


I have 4 version v3 with adapter board,and the 5 i got have version v3.1a no adapter board and heatsinks are the same I see you added on version v3.1b much better heatsinks


I cut the trace between +5 v and the header pin, then added a small jumper from the header pin to the +3.3 v, plugged in my LI-ion 7.4 pack to the EZ-B and measured 2.97 vdc between Vcc and Gnd. Using some jumpers connected the WiFi board to the EZ-B 3.3v header pins and although the WiFi board would turn on the LED it never changed from steady on to 60 ipm flashing. When in Auto mode on the WiFi board option, the LED flashes to indicate it has connected to the ASUS router. Changed the EZ-B back to +5 v and connected the Bluetooth Class 1 device and was able to connect but then removed the Blutooth and connected the WiFi using jumpers to Vcc and GND and the EZ-B LED goes dark. Also the 3 leds on the WiFi board flash and go out. Directly connecting the WiFi board to a 3.7vdc LI-ion power pack boots the WiFi board back to the 60 ipm state but still no connection can be established to the EZ-B using the Virtual com port with the WiFi IP address assigned to it by the ASUS router and populated in the virtual com port view.


Monday looking to bread board the design using a stable supply to see whats going on what WIFI board are you using,i have USR-WIFI232-B