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By: Anonymous: linxdev () on Thursday, August 25 2011 @ 01:24 PM PDT

Anonymous: linxdev

I've also seen this

PHP Formatted Code

avrdude -V -F -C /etc/avrdude.conf  -p atmega328p -P /dev/ttyUSB0 -c stk500v1  -b 115200 -U flash:w:tmp/k4l_keyer.hex

avrdude.bin: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.02s

avrdude.bin: Device signature = 0x1e950f

avrdude.bin: NOTE: FLASH memory has been specified, an erase cycle will be performed

             To disable this feature, specify the -D option.

avrdude.bin: erasing chip

avrdude.bin: reading input file "tmp/k4l_keyer.hex"

avrdude.bin: input file tmp/k4l_keyer.hex auto detected as Intel Hex

avrdude.bin: writing flash (24774 bytes):

Writing | ################################################## | 100% 20.71s

avrdude.bin: 24774 bytes of flash written

avrdude.bin: safemode: lfuse changed! Was ff, and is now 0

Would you like this fuse to be changed back? [y/n] n

avrdude.bin: safemode: hfuse changed! Was da, and is now 0

Would you like this fuse to be changed back? [y/n] n

avrdude.bin: safemode: efuse changed! Was 5, and is now 0

Would you like this fuse to be changed back? [y/n] m

avrdude.bin: safemode: Fuses OK

avrdude.bin done.  Thank you.

cfowler@compaq-desktop:~/Dropbox/Arduino/src/K4L_Keyer$ ~/Dropbox/Downloads/snoop -b 1200 -s /dev/ttyUSB1

Connected to /dev/ttyUSB1.  Enter Ctrl-\,q to exit.

^Ccfowler@compaq-desktop:~/Dropbox/Arduino/src/K4L_Keyer$ ~/Dropbox/Downloads/snoop -b 9600 -s /dev/ttyUSB1

Connected to /dev/ttyUSB1.  Enter Ctrl-\,q to exit.

^Ccfowler@compaq-desktop:~/Dropbox/Arduino/src/K4L_Keyer$ make upload

#stty -F /dev/ttyUSB0 hupcl

avrdude -V -F -C /etc/avrdude.conf  -p atmega328p -P /dev/ttyUSB0 -c stk500v1  -b 115200 -U flash:w:tmp/k4l_keyer.hex

avrdude.bin: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.02s

avrdude.bin: Device signature = 0x1e950f

avrdude.bin: NOTE: FLASH memory has been specified, an erase cycle will be performed

             To disable this feature, specify the -D option.

avrdude.bin: erasing chip

avrdude.bin: reading input file "tmp/k4l_keyer.hex"

avrdude.bin: input file tmp/k4l_keyer.hex auto detected as Intel Hex

avrdude.bin: writing flash (24774 bytes):

Writing | ################################################## | 100% 17.04s

avrdude.bin: 24774 bytes of flash written

avrdude.bin: safemode: Fuses OK

avrdude.bin done.  Thank you.

The first time it seems to fail but the second time it works. Still can't do 9600 but the device is up.

By: Anonymous: linxdev () on Thursday, August 25 2011 @ 02:23 PM PDT

Anonymous: linxdev

I am so happy. This is fixed!

I'm hoping you can explain technically why.

I have 2 TTL cables. One is a full blown MAX232. The other was designed for ICOM radios. It has both RX and TX on the tip and then ground. So it is a mono 3.5mm. Not knowing how the Arduino would like its TX and RX attached to TIP I chose only to see stuff coming from the chip.

On my GPS I only receive to. So in both cases the RX of the ATMega328 was disconnected.

The test works on the UNO because even if I had only tapped into the TX the RX would have been connected to the USB-TTL chip on that board. I had a hunch and hooked up the RX of my MAX232 to the RX of the ATMega328.

9600 works! No delay!!

Now I want to know why Smile

Chris

By: Windell (offline) on Thursday, August 25 2011 @ 03:20 PM PDT

Windell

Well, that's definitely good news. I have not come across this situation before, but I'm very glad that it is working and that you were able to find the cause (if not an explanation).

My initial assessment, without looking into it in great detail: The Arduino serial library sets up an interrupt to detect (and store) incoming data. Something is going wrong in that process if the RX line is not hooked up to anything. You might be able to defeat it by (a) disabling interrupts-- which would also make delay() not work, or (b) hooking that line through a resistor to ground or Vcc.

Windell H. Oskay
drwho(at)evilmadscientist.com
http://www.evilmadscientist.com/