- Tue Jun 28, 2016 8:14 am
#49908
I have checked the voltage at GPIO15, GPIO2 and GPIO0 pins with the following results:
GPIO15 = 0.0v
GPIO02 = 1.29v
GPIO0 = 1.84v (and 0.0v on programming mode)
Esp8266 is powered by an AP2112K-3.3 and Vcc measured voltage is 3.29v instead of a nominal of 3.3v.
AP2112 doesn't get hot so I assume that my multimeter has an error of 0.01v. That is to be considered in the other voltages measured.
According to ESP8266EX Hardware User Guide v0.7 document, High level is >0.75Vcc and Low level is <0.25Vcc. That is H>2.475v and L<0.825v (please, correct me if I'm wrong). So something is not working properly...
More hardware details:
GPIO15 is pulled down through a 10k resistor and GPIO2 is pulled up by another 10k resistor.
GPIO0 is pulled up through a smd led in series with a 1k resistor (I use a jumper to short this pin to gnd when programming).
To force the proper voltage, I soldered a 330ohm resistor in parallel with the 10k pull up resistor connected to GPIO2. Additionally, I soldered another 330ohm resistor in parallel with the smd led and 1k resistor I mentioned before.
It doesn't make any difference. Does it mean that the chip is damaged??
Hope someone can help!
Thanks,
Miguel.
GPIO15 = 0.0v
GPIO02 = 1.29v
GPIO0 = 1.84v (and 0.0v on programming mode)
Esp8266 is powered by an AP2112K-3.3 and Vcc measured voltage is 3.29v instead of a nominal of 3.3v.
AP2112 doesn't get hot so I assume that my multimeter has an error of 0.01v. That is to be considered in the other voltages measured.
According to ESP8266EX Hardware User Guide v0.7 document, High level is >0.75Vcc and Low level is <0.25Vcc. That is H>2.475v and L<0.825v (please, correct me if I'm wrong). So something is not working properly...
More hardware details:
GPIO15 is pulled down through a 10k resistor and GPIO2 is pulled up by another 10k resistor.
GPIO0 is pulled up through a smd led in series with a 1k resistor (I use a jumper to short this pin to gnd when programming).
To force the proper voltage, I soldered a 330ohm resistor in parallel with the 10k pull up resistor connected to GPIO2. Additionally, I soldered another 330ohm resistor in parallel with the smd led and 1k resistor I mentioned before.
It doesn't make any difference. Does it mean that the chip is damaged??
Hope someone can help!
Thanks,
Miguel.
