#memdude Use USBtinyISP to read and write Microchip 25LCxx EEPROM devices
The software is written in Python and demonstrates use of PyUSB using USBtiny as USB connected I/O device.
For schematics of USBtinyISP, see https://learn.adafruit.com/assets/6834
It would be wise to replace R7 and R4 with a lower value somewhere around 500 ohms, as 1.5K may cause the clock signal distortion to the point wher false clock pulses will be detected, depending on your setup.
AVR PORTB bit numbers 25LCxxx wiring
in USBtinyISP
+--------+
0 - LED VCC -+ 1 8 +- VCC
1 MISO -+ 2 7 +- VCC
2 VCC -+ 3 6 +- SCK
3 GND -+ 4 5 +- MOSI
4 - RESET +--------+
5 - MOSI
6 - MISO
7 - SCK