SCOPING TX DURING A ESP SYNCH FAIL
Posted: Sun May 08, 2016 2:59 amSynch fail is a common thread on this forum and I have been getting a lot of synch fail signals as well as comms fails ( The IDE does not seem to shut down the USB driver at the end of each operation, though it works fine in RfDuino board, but lets leave that for later)
Using IDE 1. 6.8 and Adafruit Huzzah board ( same thing with ESP generic)
Using an RFduino USB/Uart that is 3.3V rated, TX/RX and Reset only ( not using reset)
Using a separate 3.3V supply to ESP
Out with the trusty scope to have a look and everytime I have a synch fail the waveform on ESP RX is less then 1V p-p. so perhaps the handshake is failing due to lack of voltage signal and hence sycnh problems.
If I do get a successful download then a good waveform 3Vp-p
Also I have noticed that if I send single characters via Term at 115600 baud as a test then I often see that the character does not 'reach' the Rx pin on the ESP when the ESP is in upload mode yet there is no problem that I can see when the ESP is powered down. Again a good 3.3Vp-p
Is there a possibility of an impedance mismatch, or a strange hardware mismatch in the ESP? Has anyone else scoped the TX/RX?
My scope is not so flash that I can capture and download to this site. I would be interested in comments and waveforms.
Using IDE 1. 6.8 and Adafruit Huzzah board ( same thing with ESP generic)
Using an RFduino USB/Uart that is 3.3V rated, TX/RX and Reset only ( not using reset)
Using a separate 3.3V supply to ESP
Out with the trusty scope to have a look and everytime I have a synch fail the waveform on ESP RX is less then 1V p-p. so perhaps the handshake is failing due to lack of voltage signal and hence sycnh problems.
If I do get a successful download then a good waveform 3Vp-p
Also I have noticed that if I send single characters via Term at 115600 baud as a test then I often see that the character does not 'reach' the Rx pin on the ESP when the ESP is in upload mode yet there is no problem that I can see when the ESP is powered down. Again a good 3.3Vp-p
Is there a possibility of an impedance mismatch, or a strange hardware mismatch in the ESP? Has anyone else scoped the TX/RX?
My scope is not so flash that I can capture and download to this site. I would be interested in comments and waveforms.