- Mon Apr 18, 2016 3:57 pm
#45747
I'm using an ESP8266-03, on a breadboard with a 1000uf cap across the power rails.
When I have the following configuration, I can upload to the board by hitting "upload" in the Arduino IDE:
FTDI serial cable
CH_PD - pullup
GPIO0 - pulldown
GPIO15 - pulldown
All pullup and pulldown resistors are 10k.
If I keep that configuration, and put the Sparkfun serial breakout board in place of the FTDI cable, I can still upload, so my TX, RX, and ground wires are all going to the proper places, and the Sparkfun serial breakout board is working correctly.
If I try connecting as per this connection diagram: http://esp8266.github.io/Arduino/versio ... -and-usage I cannot upload to the board.
What I currently have is:
Sparkfun serial breakout
CH_PD pullup, connected to RTS on breakout
GPIO0 - pullup, connected to DTR on breakout
GPIO15 - pulldown
I tried putting an oscilloscope on the DTR and RTS lines, to see if they were actually being wiggled by the Arduino IDE.
The RTS line appears to start high, go low, and then abruptly become extremely noisy, with what looks like about 2.1v peak-to-peak noise at a 3v DC offset. The DTR line starts high, and does the same thing. They each pulse low three times, and then the IDE tells me that the upload failed.
The noise is also very visible on the TX and RX lines, GPIO0 (where it appears worst), and to some extent on all pins.
If I disconnect the DTR and RTS lines, and put them on the scope, they're clean, so this seems to be some interaction with my ESP8266 and the DTR/RTS connections on my serial converter, but I'm at a loss as to what's causing it.
I have a 1000uf cap across the power supply rails for the breadboard (removing it doesn't help), so I don't think it's a power droop, but the noise also appears on V+ at the same time, although at a lower amplitude. It doesn't appear when there's a pulldown on GPIO0, the first configuration that I listed.
I'm going to try another ESP8266-03 and will post again if that fixes anything.
When I have the following configuration, I can upload to the board by hitting "upload" in the Arduino IDE:
FTDI serial cable
CH_PD - pullup
GPIO0 - pulldown
GPIO15 - pulldown
All pullup and pulldown resistors are 10k.
If I keep that configuration, and put the Sparkfun serial breakout board in place of the FTDI cable, I can still upload, so my TX, RX, and ground wires are all going to the proper places, and the Sparkfun serial breakout board is working correctly.
If I try connecting as per this connection diagram: http://esp8266.github.io/Arduino/versio ... -and-usage I cannot upload to the board.
What I currently have is:
Sparkfun serial breakout
CH_PD pullup, connected to RTS on breakout
GPIO0 - pullup, connected to DTR on breakout
GPIO15 - pulldown
I tried putting an oscilloscope on the DTR and RTS lines, to see if they were actually being wiggled by the Arduino IDE.
The RTS line appears to start high, go low, and then abruptly become extremely noisy, with what looks like about 2.1v peak-to-peak noise at a 3v DC offset. The DTR line starts high, and does the same thing. They each pulse low three times, and then the IDE tells me that the upload failed.
The noise is also very visible on the TX and RX lines, GPIO0 (where it appears worst), and to some extent on all pins.
If I disconnect the DTR and RTS lines, and put them on the scope, they're clean, so this seems to be some interaction with my ESP8266 and the DTR/RTS connections on my serial converter, but I'm at a loss as to what's causing it.
I have a 1000uf cap across the power supply rails for the breadboard (removing it doesn't help), so I don't think it's a power droop, but the noise also appears on V+ at the same time, although at a lower amplitude. It doesn't appear when there's a pulldown on GPIO0, the first configuration that I listed.
I'm going to try another ESP8266-03 and will post again if that fixes anything.
