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Topic: Using an FTDI cable (Read 646 times) previous topic - next topic

Colaboy

Hi.
Is there a knack to programming a standalone chip using an FTDI cable?
I have tried allsorts and I just can't upload a sketch no matter what I try.
I can upload one just fine using my Uno, taking the chip out and using jumper wires.
I know the cable is working as it is a recognised com port and when attached to a working chip, it sends serial data back and forth.
I think I read somewhere that the timing of pressing reset is crucial. I have approached this in a very methodical manner(timing, gaps etc.) but to no avail.
As the Uno sorts the reset out for me but the FTDI cable doesn't, I think this may very well be the problem.

Any ideas?

Thanks in advance.
Colaboy

CrossRoads

Is your chip set up to look like a minimal Arduino? Crystal/caps or resonator, reset pullup resister?
Adding those few components might do it.

Assuming you have a bootloader on the chip already.  If not, you need to resolve that first.
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.

shelleycat

When uploading, press shift, this shows the verbose output.   You need to press the reset when (or just before) the first set of 3 or so lines appear when the serial protocol starts to query the bootloader.  Have a look at the verbose output on a good upload to your uno to get the idea.

Colaboy

Hi, thanks for that.
Yes, everything is wired up correctly.
When I upload with the Uno (either via jumper wires or actually placing the chip in the Uno) everything works perfectly.
The chips are bootloaded. I even have both Uno and Duemilanove bootloaders on different chips. Neither of which want to work.

Thanks for that Shellycat.
I'll check that out, thank you!

Thanks
Colaboy

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