Use this forum to chat about hardware specific topics for the ESP8266 (peripherals, memory, clocks, JTAG, programming)

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By arduic
#28781 So I've been working with my ESP03 for a while now, more specifically I've been working with 4 of the GPIO and 2 of the PWM on the ESP03 so my circuit to flash firmware is a bit different then normal. However, I moved the other day and when I got to my house to work on my ESP it seems to be in a partially functional state. First off I can still flash new firmware to it, the makefiles all work fine and the upload script appears to notice if I say do not pull down the proper GPIO. So I can at least say that the UART channel and internal circuit to push code onto the FLASH is working. That's where my luck ends though, I used to see my ESP on my network usually under the name ESP7B032 or some other such combination of numbers (don't have it with me right now sorry). Even worse though, basic example code no longer seems to function, as a test I uploaded the blinky code to the ESP, sure enough the GPIO goes HIGH but it stays HIGH. I tried commenting out the code and just initializing the GPIO and pull LOW, nope still the GPIO is HIGH. I'm not sure how destroyed my ESP is / if it's recoverable and was hoping someone could tell me because otherwise I'm three weeks out :(
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By kenn
#28782 What are you seeing on the serial terminal from your ESP-03?

You can try adding serial out statements to the Blinky example to confirm it makes it to the LED-change lines, echo the GPIO port status and value, etc.
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By arduic
#28783 That actually brings up some really strange behaviour. The USB-Serial setup I have should blink a light whenever Rx or Tx is fired (which it does when I upload code). However, if I am not actively listening on ttyUSB0 via GtkTerm the lights will go off even if the ESP was told to constantly stream say "." The second I tell GtkTerm to listen to my UART channel though the RX light on my chip goes crazy and my GtkTerm just starts printing garbage. I tried changing the baud rate but it just seems to print different garbage if I do that. My guess is there is a steady stream of something (not sure what) is coming in but I do not own a Scope to check.
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By kenn
#28850 That suggests a possible problem with your current circuit...

Can you breadboard just a basic flash & LED circuit with an ESP-03, and try the blinky example there?