Combo USBasp + extra with bootloader. Possible?
Posted: Fri Feb 10, 2012 7:21 pm
Hi. I'm driving myself batty staring at schematics and trying to figure out if this is easy or impossible or somewhere in between...
So let's say there's a device - not of my design, but which I want to flash periodically. I can hook a USBasp up to it, no problem. But... I also want to interface with the device beyond merely flashing. So I make an add-on board that does some heavy lifting and then communicates with the target via SPI.
Can my add-on board act BOTH as the interface to the target 95% of the time, but also be its programmer to flash firmware via USB periodically? And, can my add-on board have the bootloader in it so that I can also flash the add-on board (again, via USB) when I need to? So the same AVR is a bit of a Jeckyl and Hyde. At one time, its a USBasp programmer for updating the target via USB while at another time its something entirely different for communicating with the target via SPI AND it, itself, can be updated via USB.
I hope that's clear.
So let's say there's a device - not of my design, but which I want to flash periodically. I can hook a USBasp up to it, no problem. But... I also want to interface with the device beyond merely flashing. So I make an add-on board that does some heavy lifting and then communicates with the target via SPI.
Can my add-on board act BOTH as the interface to the target 95% of the time, but also be its programmer to flash firmware via USB periodically? And, can my add-on board have the bootloader in it so that I can also flash the add-on board (again, via USB) when I need to? So the same AVR is a bit of a Jeckyl and Hyde. At one time, its a USBasp programmer for updating the target via USB while at another time its something entirely different for communicating with the target via SPI AND it, itself, can be updated via USB.
I hope that's clear.