--- ../avrdude.old/ft245r.c 2013-09-22 17:00:01.413993533 +0200 +++ ft245r.c 2013-09-22 20:14:52.724413842 +0200 @@ -296,6 +296,10 @@ return 0; } +static int set_sck(PROGRAMMER * pgm, int value) { + return set_pin(pgm, PIN_AVR_SCK, value); +} + static int set_reset(PROGRAMMER * pgm, int value) { return set_pin(pgm, PIN_AVR_RESET, value); } @@ -418,6 +422,12 @@ */ static int ft245r_initialize(PROGRAMMER * pgm, AVRPART * p) { + /* Apply power between VCC and GND while RESET and SCK are set to “0”. In some systems, + * the programmer can not guarantee that SCK is held low during power-up. In this + * case, RESET must be given a positive pulse of at least two CPU clock cycles duration + * after SCK has been set to “0”. + */ + set_sck(pgm, OFF); ft245r_powerup(pgm); set_reset(pgm, OFF); @@ -425,7 +435,11 @@ set_reset(pgm, ON); usleep(5000); // 5ms set_reset(pgm, OFF); - usleep(5000); // 5ms + + /* Wait for at least 20 ms and enable serial programming by sending the Programming + * Enable serial instruction to pin MOSI. + */ + usleep(20000); // 20ms return ft245r_program_enable(pgm, p); }