Arduino Pro mini + FTDI

Hi everyone!

I know there are a lot of subject about how to connect ftdi & arduino pro mini already, but after all tips, mine is still not working :confused:

Here is the situation : (Arduino pro mini 3.3V atMega 328p)

all the pins are connected :

FTDI - PROmini :
DTR-DTR (depending the forums, it said to put the one from the ftdi on ground or on the other dtr, but have tried both, still not working)
VCC-VCC (little jumper on ftdi on 3.3 of course)
RX - TX
TX-RX
CTS - GND
GND-GND

On the FTDI : red led always ON.
On the aduino pro mini : I have th red power led ON and still, and another red led blinking one time per second (like if the blink exemple was preloaded) so apparently my arduino pro mini is not broken.

On the arduino IDE, i have the following failure warnings :

Using Port : COM5
Using Programmer : arduino
Overriding Baud Rate : 57600
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0xdd
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0xdd
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x77
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0xf7
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0xdd
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x77
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0xf7
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0xc7

avrdude done. Thank you.

I’ve tried to change usb port, update drivers, change usb cable, change port in the software, change board… nothing works… and i’ve tried with another arduino pro mini from the original arduino firm, doesn’t work either. (i’ve tried juste with an arduino Uno, and the sketches are loaded and works…)

i’m really desesperate.

Do you have some ideas that could help me?

thanks a lot, and enjoy open source :slight_smile:

try swapping the TX and RX lines as that;' normally what fixes it.

TX should go to RX and vice versa.

As I mentionned in the description, it was already done, but thx :slight_smile:

Are you sure you are applying 3.3 volts also. Some FTDI adaptors don’t supply 3.3 but actually supply 5V and you should double check with a DVM.

I don’t use CTS at all (nothing connected)

Yes i'm sure, I have a little piece that allows me to choose between 5 and 3.3 V. At the beginning I didn't use CTS at all either, but in some forums they connected it also so I tried it but doesn't change anything.

Even with the switch set at 3.3 please check as some of them still put 5V on the V pin.

See HERE

Ok i've tested it and the connections gives 3.3 or 5V depending the position.

Might it be a baud rate issue? because it seems that ftdi is more likely to run with 9600 instead of 57600, but i've tried to change it in the configuration pannel of COM ports and still doesn't work...

I know have the following message :

Using Port : COM5
Using Programmer : arduino
Overriding Baud Rate : 57600
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0xdd
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0xdd
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x77
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0xf7
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0xdd
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x77
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0xf7
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x77

avrdude done. Thank you.

Can you see the FTDI in device manager etc. ?
Do you have the correct drivers installed for it ?

I've uninstalled/reinstalled it several times, I see it in device manager... have the correct drivers ... I honestly don't know what I can do more... :confused:

Have you tried a loopback test to the FTDI ?
Just to rule it out,

Also can you post a decent picture of it or a link to where your purchased it ?

Here is a picture of the FTDI connected to the Arduino promini. The little red led in the corner of the arduino blinks once per second.

What do you mean by loopback test? If it is to wire Rx and TX on the ftdi, type something in the serial monitor and see what I get back, it is not working. Well, I have something back, but not what I’ve written :confused:

If you are not getting anything original back from just the FTDI then yes a baud rate issue.