README.md
Add the "tinysensor" board definition and bootloaders to the ATTinyCore:

$ make init


Build the "tinysensor" sketch:

$ make upload term
$ make NODE_ID=5 upload


To generate the bootloader file, apply "optiboot/optiboot.patch" to the optiboot 
source tree:

$ patch < optiboot.patch
$ ENV=arduino make attiny84 BAUDRATE=19200 AVRFREQ=8000000L


This will create a file optiboot_attiny84.hex for a chip clocked at 8MHz.

For a 1MHz part:

$ ENV=arduino make attiny84 BAUDRATE=9600 AVRFREQ=1000000L