MC68705 microcontrollers come with a program in mask ROM that can burn the chip's EPROM with just a little external hardware. The datasheet shows the schematic. I wanted to program some 68705s, but didn't have a 4040 counter handy and didn't want to have to erase and reprogram an EPROM each time, so I wrote code for a Microchip PIC 18F46K22 to replace the counter and EPROM.