I intent to use a TinyUSB programmer to program a board I'm putting together.
It will run on 3.3V with external 8MHz crystal. I see there is an option for 3.3V 8MHz but no idea if its internal or external clock.
So the question is, can I use the Arduino Pro boards to program it? No need to bootload it, I can happily live with the ICSP.
Thanks and sorry if it has been answered before. I get a ton of results if I search the forum, but most of which are on how to bootload the chip.
Yes, Arduino Pro or Pro Mini board selection on menu, ATmega328 (3.3V, 8 MHz) processor selection. The Pro Mini of that variety has an external crystal. So, you are essentially building something like a Pro Mini. I recommend studying schematics and Eagle board files for the Pro Mini as you are getting yours ready.
Run the Burn Bootloader option at least once, even if you do not intend to use the bootloader. This is because during the Burn Bootloader is when the fuses are set. Then from that point on you can use your ICSP programmer and the menu option Upload Using Programmer.
To do advanced stuff, you can go in the IDE preferences and checkmark "Show verbose output during upload" and go ahead and do the Burn Bootloader, and the avrdude command lines for unlocking and erasing the chip, and for writing the bootloader and setting the fuses will be shown to you. Then upload a sketch with Upload Using Programmer and the avrdude command will be shown to to you for uploading a sketch. You will then have the info you need to do command line stuff, such as set the fuses to something different or upload a hex file.