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macOS - Aruino IDE ...
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[Solved] macOS - Aruino IDE - How to fix "pyserial or esptool directories not found next to this tool" error (ESP8266)

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Famed Member Admin
Joined: 11 years ago
Posts: 2724
Topic starter  

When switching to Big Sur, somehow the ESP8266 tools for the Arduino IDE broke ... and one cannot upload compiled sketches any more.

An example of this error:

pyserial or esptool directories not found next to this tool.
An error occurred while uploading the sketch


This affects at least ESP8266 Core version 2.7.4 and 2.7.2 (I'm running Arduino IDE version: 1.8.13 right now).

The fix:

  1. Open the file
  2. Comment out lines 29 and 30 and add these lines:
       iokit = ctypes.cdll.LoadLibrary('/System/Library/Frameworks/IOKit.framework/IOKit')
       cf = ctypes.cdll.LoadLibrary('/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation')

The code should look something like this, save it and try again ... this fixed it on my Mac:

from import list_ports_common

#iokit = ctypes.cdll.LoadLibrary(ctypes.util.find_library('IOKit'))
#cf = ctypes.cdll.LoadLibrary(ctypes.util.find_library('CoreFoundation'))
iokit = ctypes.cdll.LoadLibrary('/System/Library/Frameworks/IOKit.framework/IOKit')
cf = ctypes.cdll.LoadLibrary('/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation')

kIOMasterPortDefault = ctypes.c_void_p.in_dll(iokit, "kIOMasterPortDefault")
kCFAllocatorDefault = ctypes.c_void_p.in_dll(cf, "kCFAllocatorDefault")

Joined: 1 second ago
Posts: 0

Very useful,

It worked for me (iMAC BIG SUR).

thanks for sharing

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