Arduino bootloading

Using Arduino Microcontrollers
1

Hi everyone! I am making a standalone project using ATmega328P in its TQFP32 package, since I have limited space to work with. I have burned bootloaders on this chip before using a simple Arduino shield and the DIP28 package of the chip.

My question is, if I solder my entire project to a PCB including the chip, could I burn the bootloader using a connector to the corresponding pins?

I am asking this because when uploading the ISP you must not have anything connected to the board, and the bootloader shield I used has like 3-4 parts on it. I know that I can upload a program with everything connected to it but the mystery remains for the bootloading procedure.

2

I forgot to mention, I am using the SPI pins for my project, so if I could burn the bootloader, I should probably use a 2x4 header pins with jumpers or something.

3

Yeah, you can definitely do that. (What'd you think they meant by "In-System Programming"? :stuck_out_tongue: )

If the other stuff on those pins is high-impedance, you might not even need to take everything else off the pins (test this on the bench - I've certainly bootloaded boards with other things on those pins. Other SPI devices should have a (hardware) pullup on the CS pin to keep them from thinking the ISP is talking to them).

4

Thanks for the answer. Now that I know I can program the chip on the PCB with all the components I can sleep well :smiley: otherwise it would be a nightmare to make a suitable shield for the TQFP32 package