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If you want to go to Home Automation avoid this ESP-01 module. For a beginner this is the most complicated module to start with. So many quirks and issues.Start with a Wemos D1 mini and save yourself lots of time. Small and relatively cheap on Ebay or Bangood. You can program in Arduino IDE or Micropython.Well documented with many examples on the net.
Nice tutorial but there is one big mistake.The Arduino can NOT supply enough power to the ESP8266 when it is transmitting.Use a 5V to 3.3 V regulator to power the ESP8266. Also put 100 microfarad + 100nF across3.3 V to filter the power supply.
Very good job to cram so much in just 8k memory.Have you considered to upgrade to the Attiny167 ? 16k memory.Who supplied the 8 pin programming clip ? Price ?
Why bother to struggle with pin numbers, libraries and different versions of the Arduino IDE ?There are so many incompatibility issues here with the Tiny chips.This combo works: Arduino 1.8.5 and AttinyCore. On Ebay you can buy Arduino Pro Mini for £ 1.44 with header pins including shipping. How much is your sparetime worth ?Yes, I have been there. All the way with tiny13A,45,84,85.,88.Buy some Pro Mini 3 Volts @8 MHz also so you dont have to worry with voltage dividerswhen using displays,sensors etc from the cell phone industry running at 3.3 volts max.Don't even try to use 5 volts on a 3.3 V device. It will break.