avrdude and Pl2303 USB->serial converter

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I am replacing my desktop computer with a laptop and am having trouble getting my dasa programmer to work with the laptop and a PL2303-equipped USB-to-serial converter. If I try to read a Tiny2313 using:

    avrdude -p t2313 -c dasa -P /dev/ttyUSB0 -C etc/avrdude.conf -v
the only response received is:
    avrdude: AVR device not responding avrdude: initialization failed, rc=-1
    Double check connections and try again, or use -F to override this check.
If I unplug the serial cable from the adapter and plug it directly into my old PC's serial port, the chip is read instantly without a problem.

FWIW, I notice that if the chip is programmed with a simple blinking LED "hello world" program, the LED will immediately stop blinking when the programmer's serial cable is plugged into the desktop PC's serial port. On the laptop, the blinking LED does not stop when I plug the cable into the serial adapter, but does stop blinking while avrdude tries to read the chip. Is this normal behavior for a serial adapter, or does it mean the pin configurations are different from my serial port and I need to edit the settings in avrdude.conf? The current settings are the default (reset=rts sck=dtr mosi=txd miso=cts).

I've tried increasing the delay using "-i 4000" but receive the same result. Is there something else I should try before giving up? I'm running avrdude 5.5. on Ubuntu 8.10. Thanks for any advice you might have.

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You can't do bit-banged serial ISP with a USB-RS232. Time to consider a new programmer solution.

Oh boy 'Freaks has a REAL problem - it's put this answer BEFORE the question below!!!

(Cliff)

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Quote:
You can't do bit-banged serial ISP with a USB-RS232.

Others appear to be doing it. Adafruit is selling a USB-RS232 adapter they say will work for serial ISP:

http://www.adafruit.com/index.php?main_page=product_info&products_id=18

My adapter might not be compatible, but I thought I'd see if I'm missing anything obvious that could resolve the problem before giving up.

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"note that they are slow in comparison to hardware
serial ports due to the high overhead of USB."

Even if it works, it's perhaps a solution to solve the chicken-and-egg
problem of flashing the firmware into your own real USB-to-ISP programmer,
but nothing you'd want to use in daily operation.

Jörg Wunsch

Please don't send me PMs, use email if you want to approach me personally.

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Quote:

Even if it works, it's perhaps a solution to solve the chicken-and-egg problem of flashing the firmware into your own real USB-to-ISP programmer, but nothing you'd want to use in daily operation.

Yes, you're probably right. I was actually planning to use it to program a Tiny2313 to make a USBTiny programmer. I'll just use the desktop PC while its still available to program the USBTiny chip instead. Thanks to everyone for their help.