Amazon.com: Geekstory for ATMEL 51 AVR USB ISP ASP Microcontroller Programmer Downloader with Cable + 10Pin to 6Pin Adapter Board for Ender 3 or Ender 3 Pro : Electronics
The ATMega328P From (Almost) Nothing: 5. Flashing The Microcontroller
ESU 59827 LokPilot 5 micro DCC, 6-pin Direct
Microchip Technology PIC10F202-I/P. 6-Pin 8-Bit Flash Microcontrollers - 15 pcs for sale online | eBay