I have a question about mutiple Xmega Device Firmware Upgrades. I downloaded a bootloader binary for my ATXmega128A4U from the Atmel site.
I used an Atmel ICE to program the bootloader over PDI with the binary, also I set BOOTRST to bootloader reset. I had my USB cable connected as well. After burning the binary
the XMega appeared in my windows device manager as an Atmel USB Device. I then wrote my application .hex file into flash with Atmel FLIP and all was good.
But as the .hex file is written ATXmega128A4U disappears from windows device manager and I loose the USB connection between Xmega and FLIP respectively.
I double checked the Xmega's flash memory and figured out that the bootloader binary touches only a bootloader section and my app touches only an application section.
I know that there's a possibility to force Xmega to a DFU mode with a specific pin, wich is controlled in conf_isp.h file (I have the sorce code for binary) but I have a customized board and
there are no "free" available pins on it (According to AVR1916.pdf default pin for ATXmega128A4U is PC3).
So the questions:
1) How come the USB connection with FLIP is lost after writing a .hex file?
2) What should I do to switch my ATXmega128A4U to DFU mode if I don't have an available pin on my board?
AVR1916.pdf is attached.
Appreciate any suggestions.