With the attiny84/85, it is a real hassle to re-connect the USBtinyISP programmer every time I need to re-flash the IC...
As most of my attiny84 sketch hv a SerialUSB (FTDI) with TinyDebugSerial ( Communication with Tiny's ) connected to PB0 , I found the TinySafeBoot the perfect bootloader for these attiny...
Just using a command line to send the sketch to the attiny84 with the Serial Tx/Rx lines...
TinySafeBoot ( http://jtxp.org/tech/tinysafeboot_en.htm )
The TinySafeBoot installation steps are ( not very details on the site ) :-
-
Generate the bootloader hex for attiny84 :-
tsb tn84 b1b0 ( b1 = rx/PB1, b0 = tx/PB0 ) -
Burn the bootloader to the attiny84 ( my programmer is USBtinyISP )
avrdude -c usbtiny -p t84 -U flash:w: -
Set the fuse bits
avrdude -c usbtiny -p t84 -U efuse:w:0xFE:m ( Turn on SELFPRGEN bits ) -
Use tsb to send the attiny84 hex to attiny84 using USBSerial
RESET attiny84
tsb COM5 fw blink.hex
Hope this helps ...