Hello,
We are currently working on a prototype RFID reader with a M6E-NANO.
At one point everything was functioning as intended.
Then, we had a few miscommunications between our board and the module.
We try to reset a few times and now it is not communicating anymore.
So far, at boot, the M6E-NANO always send the same thing once (At 115200 baudrate) :
ff 14 04 00 00 14 12 08 00 30 00 00 02 20 19 09 23 01 09 02 02 00 00 00 10 6c 33
I’m trying to reflash the firmware on it but using URA 5.2 give me a timeout when trying to connect to it.
We would like to know if it is possible to get back in a working state the module,
Thank you
The M6E-Nano will always send the hardware and firmware information at power-up. In your case :
ff 14 04 00 00 14 12 08 00 30 00 00 02 20 19 09 23 01 09 02 02 00 00 00 10 6c 33
translates to :
boot loader version 14 12 08 00
hardware version 30 00 00 02 TMR_SR_MODEL_M6E_NANO
firmware date 20 19 09 23 (yy yy mm dd)
firmware release 01 09 02 02
protocol bits 00 00 00 10 supported protocols: PROTOCOL_GEN2
It is not the latest version, but it should work.
Did you power with 5V ?
Do you use a USB/Serial converter that provides 5V output and not 3v3?
Maybe it got too warm, it will switch off in that case and you need to give it time to cool down.
Hi paulvha,
That’s what I thought after reading through the library that it was probably power up information.
I use both logic voltage 3V3/5V but never bypassed the logic level converter with 5V.
I use an external power source over USB at the moment (Not the same as the Serial adapter).
Last time I had it functioning was over a buck/boost converter at 5V.
It was use with an NodeMCU ESP-12E with wire solder on the 3V3 side of the logic level converter.
Strange thing I’ve observed while troubleshooting, at first I didn’t even had the power LED ON and I measure 1,09V directly on the enable pin.
I’ve try to leave it floating but same voltage and no light.
Then, I use an I/O to pull it HIGH and the 3V3 rail was now active, light on and getting the power up information over serial.
Still the module doesn’t to respond to any command.
I’ve still hope it is not totally useless since it still power up and send information.
Thank You
there should be no need to pull the enable high. leaving it floating worked all the the time.
I am a bit lost on how you connected the power and logic cabling. The 3V3 is derived from the M6E-Nano, which creates internal the 3V3 voltage from the external VCC (5V).
can you share and/or share pictures ?
I use J2 for the USB to Serial Adapter,
J2 <—> USB To Serial
TXO <—> RXD
RXI <—> TXD
GND <—> GND
I use J6 for power Input, tried with different power source.
I know I’m no supposed to have to pull high the enable pin, but If I dont, it stay at 1.09V and the internal 3V3 from the M6E-Nano doesn’t come up and running.
I still can’t get it to connect in URA to reflash it. In the transport log, I see that it try to send : FF 00 03 1D 0C with no reply.
Also I’ve tried with FTDI and Sillicon Labs serial adapter
But when using termite to send the same command, I get various reply. Is it possible that there is a problem with URA?
In the latest version 5.2, I don’t even see my Serial Interface so I use 4.3 (Only other version I found)
I know it may be hard to follow but I try to give as much information as I can.
Thanks
Edit: The 3v3 I use to pull high the enable pin is not taken from the board, I use it from an external source also.
The command ‘FF 00 03 1D 0C’ is a request to provide the hardware and firmware levels (same data as is submitted at power-up). But is not getting an answer.
If I try to measure on Enable-pin with my digital meter, it first turns off the 3v3 for a short moment, as the meter takes away the high impedance supplied pull-up voltage. Then it restores the 3V3 and I measure on the enable pin close to the provided 5V J2-VCC (not 3v3)
I am wondering with pulling enable-pin high, are you actually feeding 3v3 into the circuit “the other way around”. But as that is a high impedance internal circuit, it might not get enough power.
5V to J6+ and GND to J6- from an external supply should work. The 5V is passed with a diode to the VCC line of J2. Should be able to measure 4.3V ( 5 minus ~0.7V) on the J2 VCC connect. If not, there is a problem. Maybe also try to connect the VCC directly to the J2 VCC.
VCC itself is not a problem I think, I do Get around 4.3V on J2.
I confirm that the enable Pin Backfeed in the circuit, the LED is on a little bit DIM and get around 2.4V on the 3.3 rail having only the module GNDed and pulling externally High enable.
Looks to me the 3v3 regulator in the M6E-Nano is broken.
Maybe a last final check that the 4.3V makes it to the M6E :
-
M6E component side up.
-
J2 turned away from you, antenna pointing to you
-
On the right-hand side (whether J6 is)
-
The M6E pin right-hand top is GND.
-
the next 2 pins are connected to each other and to VCC.
Check the VCC makes it into the M6E-Nano. If it does…I would not have other ideas and consider it broken.
I already checked that in first hand when I had no sign of power, Indeed VCC reach the module at those pin.
Do you have an idea what may have cause the internal regulator to failed?
I’m sure that I didn’t short anything while testing my setup.
I was doing a couple of power cycling to validate that my MCU was picking up WiFi and detecting the module when it stop working.
Thank you
no idea. The software could not do it.
-
Maybe a (too) large spike on the incoming buck/boost power. That could be down to the quality of the supply during power on / off
-
Indeed a short on the 3V3 comes to mind, but that is exposed only on very limited places on the board and not external.
-
Maybe a bad M6E-Nano. After all, it is hardware and hardware can fail…
You could try to return it under warranty / Dead_on_arrival (DOA) to the point where you bought it.