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Project Help and Ideas » MakeFile & USB TTL/UART Module Help Please

August 25, 2009
by Nerdful_com
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I bought a USB breakout board to replace the NerdKit USB dongle and serial TTL converter board. It was really cheap on EBay (USB To TTL Converter Module cp2102 arm9 max232) and I could not refuse. Link on

I have been able to get it to work communicating with UART (send data to and from PC) without issues, but I can not load a script (C code) on to the MCU as I have to change something in the MAKEFILE I am assuming. Basically I have to use the NErdKit header to program the ATmega168, then I can use the USB board I bought without problems.

See this line in our MAKEFILE; AVRDUDEFLAGS=-c avr109 -p m168 -b 115200 -P COM12, the "avr109" lets the kit know we are setting up for suitable connection for NerdKit. If we change the avr109 to "pada", then it attempts to look for a printer port ("stk500" and "avrispmkII" is for a type of ISP, other words that can be used "ponyser", "jtag1"). I need to know what word I need to replace "avr109" with to get it to program to my new USB board.

August 25, 2009
by Nerdful_com
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When I try to upload any code to my MCU get this error: make:

*** [project-upload] Error 1

avrdude -c avr109 -p m168 -b 115200 -P COM12 -U flash:w:project.hex:a
avrdude: ser_open(): can't open device "COM12": The system cannot find the file specified.

make: *** [project-upload] Error 1
August 25, 2009
by Nerdful_com
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I fixed/figured it out myself through much trial and error. Seems COM12 is too high, if I forced the com to become com5, then it works just fine!

Sorry for the bother...

Here's a pic: RULES!

August 29, 2009
by pedroh96
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Pretty cool, Nerdful!

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