ESP8266 Community Forum

- Thu Oct 22, 2015 12:17 am #31992 Hi,

A friend game me an esp-12 on a dev board, very similar to this (perhaps the same):
http://www.ebay.com/itm/ESP8266-WIFI-Se ... SwLVZVgSmV

I want to put it into a battery powered project, so don't want to be powering all those LEDs. I managed to desolder the esp-12 from the dev board and get it wired into a breadboard. Here's my setup.
* arduino IDE 1.6.5 with stable github.com/esp8266/arduino installed
* sparkfun FTDI Basic 3v3
* latest official FTDI drivers for mac os x 10.10
* esp-12 GND -- ftdi GND
* esp-12 VCC -- ftdi 3v3
* esp-12 TX -- ftdi RXI
* esp-12 RX -- ftdi TXO
* esp-12 GPIO15 -- pulldown 4k7
* esp-12 GPIO0 -- pulldown 4k7
* esp-12 CH_PD -- pullup 4k7
* esp-12 REST -- pullup 4k7
* esp-12 REST -- ftdi DTR

It was working fine before I desoldered it, though I think I had it wired differently. I'm pretty new to esp8266 and electronics, so it's entirely possible that I just fried something. I did check that none of the esp-12 pins/pads are shorted to their neighbors.

Here's the sketch:

Code: Select allvoid setup() {
    Serial.begin(115200);
}
void loop() {
    Serial.println("hello");
    delay(1000);
}


After uploading I try to open the serial monitor but it says /dev/tty.usbserial device isn't available. I try unplugging it, removing the GPIO0 pulldown and plugging it back in but it still can't find the device. I remove the GPIO15 pulldown, add GPIO0 pullup, and I can connect the serial monitor but no output.

Did I wire it up correctly? Did I perhaps ruin something?

- Fri Oct 23, 2015 6:00 pm #32152

Hi,

A friend game me an esp-12 on a dev board, very similar to this (perhaps the same):
http://www.ebay.com/itm/ESP8266-WIFI-Se ... SwLVZVgSmV

I want to put it into a battery powered project, so don't want to be powering all those LEDs. I managed to desolder the esp-12 from the dev board and get it wired into a breadboard. Here's my setup.
* arduino IDE 1.6.5 with stable github.com/esp8266/arduino installed
* sparkfun FTDI Basic 3v3
* latest official FTDI drivers for mac os x 10.10
* esp-12 GND -- ftdi GND
* esp-12 VCC -- ftdi 3v3
* esp-12 TX -- ftdi RXI
* esp-12 RX -- ftdi TXO
* esp-12 GPIO15 -- pulldown 4k7
* esp-12 GPIO0 -- pulldown 4k7
* esp-12 CH_PD -- pullup 4k7
* esp-12 REST -- pullup 4k7
* esp-12 REST -- ftdi DTR

It was working fine before I desoldered it, though I think I had it wired differently. I'm pretty new to esp8266 and electronics, so it's entirely possible that I just fried something. I did check that none of the esp-12 pins/pads are shorted to their neighbors.

Here's the sketch:

Code: Select allvoid setup() {
    Serial.begin(115200);
}
void loop() {
    Serial.println("hello");
    delay(1000);
}


After uploading I try to open the serial monitor but it says /dev/tty.usbserial device isn't available. I try unplugging it, removing the GPIO0 pulldown and plugging it back in but it still can't find the device. I remove the GPIO15 pulldown, add GPIO0 pullup, and I can connect the serial monitor but no output.

Did I wire it up correctly? Did I perhaps ruin something?

Hi. I am familiar with that board and reviewed it here viewtopic.php?f=29&t=5503
You may not have fried anything. Take a look at the diagrams here: https://github.com/adafruit/ESP8266-arduino
Look at how RTS is connected to Reset in the FTDI example. But you have: * esp-12 REST -- pullup 4k7
* esp-12 REST -- ftdi DTR.

I think that may be one problem.

Another problem (which can be intermittent) is an insufficient power supply from the FTDI board. In fact, there is a user comment on the Adafruit board reporting problems using one of these boards with ESP8266.

Let us know if this helps.

DrG

- Mon Oct 26, 2015 4:52 pm #32340 Got it working!

I wired up a regulator[1] as the "power supply" in that ESP8266-arduino schematic you posted. I had been experiencing some inconsistencies in fact.

The Sparkfun "FTDI Basic"[2] that I have doesn't have an RTS line, just DTR and CTS. I just realized that Sparkfun has a "ESP6266 Thing"[3] so I checked its schematic[4]. So I just wired FTDI:DTR to ESP:GPIO0 as per the schematic.

The only change I did was to add a momentary button (NO) between GND and GPIO0. I held this LOW as I powered the ESP. If I didn't I got a "warning: espcomm_sync failed" when I tried to upload. This suggests to me that the DTR isn't held LOW (or not strongly enough) for the ESP to boot into "program from UART" mode.

Thanks a bunch for the help!

p.s. Note to newbies: check your connections! I found a couple of dead spots on my breadboard

[1] https://www.sparkfun.com/products/526
[2] https://www.sparkfun.com/products/9873
[3] https://www.sparkfun.com/products/13231
[4] https://cdn.sparkfun.com/datasheets/Wir ... _Thing.pdf