Hello i have a cheap ftdi that i am going to recreate on a pcb so i can flash my ATmega2560 chip onboard, the ftdi has a DTR line which is pulled low when the sequence starts but it stays low instead of going low then high after 1ms to 50ms, so i need to find out how i could create a simple circuit which when is pulled low then goes high, how can i do this, i have some simple components to hand.
my stocked parts:
103 ceramic caps
25uF aluminium caps
220uF aluminium caps
some blue ceramic caps labeled "10"
practically all common resistors values
5v zener diodes
5v switching diodes
n channel mosfets
5v reflecting diodes
can i make something using those ? Else I can get what's needed.
Many thank from Edwin
Sorry it's an atmel atMega 2560 chip on a pcb i have the serial lines and reset,5v,ground and two gpios on a pin out. So I can only flash with a ftdi. And my ftdi DTR line stay low and i need to just pluse the rest line so I need to figure out how to use this low signal to pull the reset low but then high right after.
IF I was to try this on my arduino Mega or Uno holding down the reset does not work it's a pulse going low then high to load the boot manager. So hence the dfti DTR staying low will not work if directly connected to RST.