danielnora:
Hello,I have successfully burnt the firmware to a CC2541F256 without voltage converters or any resistors, by directly connecting the DC, DD and RESET pins to an Arduino UNO with the sketch.
I didn't have success previously, I assume, because I had a bad CC2541 chip. When I switched it to a new chip, the upload worked. I don't know if it didn't work because I flashed the HostTest application (from the HostTestRelease), which might have resulted in the chip becoming non-functional.
I am still unable to use the AT commands on the CC2541, even though it is assembled as in the schematic in my previous post. I'm using P1_6 as TX and P1_7 as RX, which I suppose are the TX and RX pins in HM-10.
Daniel
Make sure you aren't sending a carriage return and line feed after the AT commands. The bolutek firmware required "\r\n" after the AT commands but the HM-10 firmware must not have these for it to accept them as commands. If the commands are sent with a carriage return and line feed, they are simply sent over Bluetooth and aren't treated as commands. When you get an "OK" back from sending "AT" it's a good idea to issue the "AT+RENEW" command to reset all the settings. In my case, the Bluetooth module did not even broadcast its name until I issued that command. Good luck!