My laptop is Dell E1505. It does not have a serial port. So I am using the USB Jtag. The USB_to_Serial driver allots COM7. I am not able to assign COM1 using the device manager.
go to control panel/system/hardware/device manager
inside Ports (COM & LPT) tree find your USB-COM port
open properties of this port
switch to ‘port settings’ tab
click ‘Advanced’ button
select COM1 or COM2, they must NOT show ‘(in use)’, clik OK twice
right click to any item in hardware tree, click ‘scan for hardware changes’, after some time your com port number must be updated
enjoy
if you able to connect to JTAG and it works, then in the same ‘properties’ page and inside AVR Studio I suggest to change the port speed to 115200, this will increase debug speed a lot.
Additional information about OLIMEX AVR-USB-JTAG (a short FAQ from me):
if you are trying to upgrade a firmware through AVR Studio/AVR Prog be sure to have good external power supply, do not use USB power for JTAG!
pins 4 and 7 on JTAG socket must be BOTH connected to +5v
if AVR-JTAG is started properly, the LED must be ON. Once you AVR Studio successufuly connected to JTAG, the LED goes OFF. During debug session/program run on target/etc the LED must be flashing time to time (during mode change, program update etc). This means everything works.
disconnect JTAG power and JTAG USB port after any changes made (like firmware upgrade, target change etc). Then replug again. It is a hardware reset for JTAG
I had received a reply, in the meanwhile, from Olimex, telling me that I have a old version and that I should follow the same upgrade procedure as given for the serial port jtag.
But I was reluctant to do that. It is anyway working with my old version of AVR Studio, so why take the risk ?
After I got your reply, I tried every single step as told by you.
I started the upgrade through AVR Studio. A short while after the upgrade started, my mains power failed and the upgrade got aborted.
I thought that was the end of my JTAG because AVR studio complained “improper erasure” after I restored the power supply and tried programming the flash once again.
But I was in for a pleasant surprise !! After I cancelled that upgrade screen, my JTAG connected to the target board and I was able to download the program to the target.
I guess that Olimex board can not be upgraded properly, unless you switch the bottloader fuse by serial programmer, as recommended in their html page about firmware update.
So by default this fuse is disabled meaning that upgrade can not work. I had the same strange behavior with my AVR-JTAG-USB and this is a NEW board from Olimex, just two months old. So I suspect there is some compatibility issues between original Atmel JTAG ICE and Olimex board.
I don’t know really… since I recovered from the same failure by firmware upgrade - now it works fine 8)