It's working Vice-Versa, Traditionally uC's need high power to get into programming mode like PIC's (well without bootloader) but this is programming at 3.3v and vomiting at 5v that's strange ,ok so which one USB to Serial Adapter are you using?
It's working Vice-Versa, Traditionally uC's need high power to get into programming mode like PIC's (well without bootloader) but this is programming at 3.3v and vomiting at 5v that's strange ,ok so which one USB to Serial Adapter are you using?