I find it very suspicious you had to use -F
I read the post of riyadhalnur yesterday and did a test using an Uno not a Leonardo because I do not have one. I tried to check if using the -F option will change the error message thrown by avrdude in case a SPI connection is broken.
The reported error changes but it remains an evident error.
If I have good connections between Arduino and the target AVR no error is displayed.
My settings:
Arduino Uno + ArduinoISP as in ISP Programmer
Connections: Arduino Uno (SS, Miso, Mosi, SCK) -> taget on breadboard Atmegae328p (Reset, Miso, Mosi, SCK).
- Good ISP connections:
c:\>avrdude -P COM3 -b 19200 -c avrisp -p m328p -n
avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.17s
avrdude: Device signature = 0x1e950f
avrdude: safemode: Fuses OK
avrdude done. Thank you.
- SS->RESET connection broken
c:\>avrdude -P COM3 -b 19200 -c avrisp -p m328p -n
avrdude: stk500_program_enable(): protocol error, expect=0x14, resp=0x50
avrdude: initialization failed, rc=-1
Double check connections and try again, or use -F to override
this check.
avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51
avrdude done. Thank you.
- SS->RESET connection broken but -F added
c:\>avrdude -P COM3 -b 19200 -c avrisp -p m328p -n -F
avrdude: stk500_program_enable(): protocol error, expect=0x14, resp=0x50
avrdude: initialization failed, rc=-1
avrdude: AVR device initialized and ready to accept instructions
avrdude: Device signature = 0x000000
avrdude: Yikes! [b]Invalid device signature[/b].
avrdude: Expected signature for ATMEGA328P is 1E 95 0F
avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51
avrdude done. Thank you.
Conclusion: -F does not fix anything as long as you have wrong SPI wiring and you do not get the "use -F" error message if you have good connections, excepting the case when the AVR oscillator (external) does not work or the target AVR is not powered!