USB to TTL serial header cable flakiness.

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toddfun
 
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USB to TTL serial header cable flakiness.

Post by toddfun »

I have a USB to TTL serial header cable I purchased with my sanguino board that always added flaky. I have lived with it for a year now and wanted to ask if I maybe have a bum cable or if this is normal flakiness.

When I first connect my cable I can upload a sketch just fine without pushing the reset button on my board. This is normal because the sanguino board comes with auto-rest support.

The 2nd, 3rd, .... and forever attempt at loading a sketch fails to make a connection being there was no auto-rest signal from the serial header cable. If I disconnect my cable and reconnect it then it works again. I don't have to restart the Arduino IDE or the board which is wall wart powered.

Using my meter I can see that the 1st attempt to upload a sketch is preceded by a rest from 5v to 0v and back to 5v on the serial header cable pin (green in my case). I can meter this even with the serial header cable disconnected from the board.

Likewise when I attempt the 2nd, 3rd and soon uploads I don't get a rest at the serial header when connected and when not connected to the board.

I must pull the cable out of the computer and then reconnect before I can reload again with the auto-rest working. Of course I don't do that I just press the rest button on the board before clicking the upload sketch button which works 100% of the time. Kind of a pain when I should have to remember to do such a task each time.

I have tried 3 different computers and also downloaded the most current version of Arduino "0016" and uninstalled/reinstalled the FTDI USB Drivers that come with the download. No luck, same flaky problem.

Is my cable bad or is this just something we all have to live with when using this type of cable and driver when uploading a sketch to a sanguino or other ardinuo derivative?

Todd

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Re: USB to TTL serial header cable flakiness.

Post by adafruit »

did you Set RTS On Close?

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toddfun
 
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Re: USB to TTL serial header cable flakiness.

Post by toddfun »

WOW! that was it. I have been living with this for a year now. It auto-resets each and every time now and starts running the sketch auto too. Sooo much easier this way!
Thanks a TON.

I'm kind of old school and try to figure things out myself mostly because that was the only way 25 years ago. Now that I have more time I have been getting back into electronics as a hobby but I see now, with the large on line communities, I'm going to have to change my approach and first check for solutions on sites like yours.

Thanks again.
Todd

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