Go Down

Topic: test ftdi (Read 957 times) previous topic - next topic

omega4586

hello folks,
i recently bought and ftdi : https://d3s5r33r268y59.cloudfront.net/5132/products/thumbs/2014-06-24T01:17:19.246Z-uart_hi_res.jpg.2560x2560_q85.jpg (exactly the same)
i wired it up to my atmega328p and it didn't work i re-check the wiring and all seams good, to test the ftdi and be sure that i've not made a mistake i tried to reprogramme the atmega on an arduino uno so i wired tx to rx, rx to tx, dtr to reset (without capacitor), vcc to vcc and gnd to gnd, and it didn't work, how can i be sure that my ftdi is not working (when i wire rx and tx on the ftdi and send something on the serial monitor a got it back)
thanks for help

CrossRoads

"dtr to reset (without capacitor), "
Add a series 0.1uF cap, otherwise when DTR goes low to indicate it is ready to receive data, the '328P will go into reset and stay there.
Or leave the DTR connection off, it is only needed to cause a reset to kick off the bootloader.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

avr_fred

Quote
i tried to reprogramme the atmega on an arduino uno
Of course it didn't work. A Uno does not use the FTDI chip for USB so the wrong driver is being loaded.

Select the board type "Duemilanove" and processor type ATmega328 and don't forget to add the 100nf cap in series between DTR on the FTDI and RST of the ATmega.

omega4586

thank you all for your replies,
i didn't add a capacitor when i use the ftdi on my uno, cause in the schematic the uno has already one, but when i use the ftdi on the atmega on a breadboard i add a ceramic capacitor.
i will try to select Duemilanove, is there in thing else that i have to check?

Go Up