Greetings,
I am trying to combine the Grbl Shield and Arduino Uno together to make a desktop cnc learning project, and have discovered that there are some technical prerequisites that are just assumed and perhaps I should have asked a lot more questions.
I discovered that the Arduino bootloader needs to be flashed ( pardon me if I don’t get the terminology correct at this point ) with the grbl hex file and I would need a USB AVR Programmer to accomplish this, so in looking around I discovered that Pololu had a lot of helpful information especially for me which I am grateful for, thanks very much 
I purchased the Pololu USB AVR Programmer #1300 and downloaded all the documentation and driver files and software and installed it all, and read through the PDF file about the programmer and on page 12 there is a suggestion to “Upgrade your programmer’s firmware to version 1.06 or later. See Section 9 for instructions”, in section 9 of the PDF file on page 52 there is info on how to determine the current firmware revision, I followed those instructions and found the revision to be “1010” I read further and found that I needed to download the terminal program “Br@y terminal” which I did. I downloaded the 1.06 firmware revision from Pololu.
On page 51 there is a paragraph
“To determine the programmer’s revision code in Windows: If you only see one entry for the programmer
in your Device Manager, then you have a special modified firmware version.” -------> I did in fact find this to be true and wasnt sure if I should continue forward or not at that point, I had looked further and discovered the rev as being “1010” so I thought I would follow the intructions for using the “Br@y terminal” program to try and update the firmware.
To make a long story shorter , I am now in this area--------> "Upgrading Firmware
To upgrade your programmer’s firmware, follow these steps:
-
Once the programmer is in bootloader mode, it will appear to your computer as a new device called
“Pololu pgm03a Bootloader”.
Windows 7, Vista and Linux: The driver for the bootloader will automatically be installed.
Windows XP: When the “Found New Hardware Wizard” is displayed, follow steps 4–6 in Section
3.a to get the driver working. >>>>>>>> (Done) -
Once the bootloader’s drivers are properly installed, the green LED should be blinking in a double heartbeat
pattern, and there should be an entry for the bootloader in the “Ports (COM & LPT)” list of your
computer’s Device Manager in Windows. >>>>>>>> (Done) -
Use a terminal program (such as Br@y Terminal [sites.google.com/site/terminalbpp/]) to connect to the
bootloader’s virtual serial port. In Windows, you can determine the port name of the bootloader (e.g. COM5)
by looking in the Device Manager. In Linux, you can determine the port name (e.g. /dev/ttyACM0) by
running dmesg. You can use any baud rate. >>>>>>>> (Done) -
Type the following lower-case letters into your terminal program to send them to the bootloader:
fwbootload. After each letter is sent, the bootloader should echo back the upper-case version of that letter.
After you have finished typing this sequence, you should see “FWBOOTLOAD” as the output from the
bootloader in your terminal program, and the programmer’s yellow LED should be on. >>>>>>>> (Done)
Below is where I am stuck the terminal program will not accept the lower case “s” and now I am dead in the water and do not know if I should have even gone this far.
- Now send lower-case “s”. The bootloader will spend a few seconds erasing the current firmware and
settings, and then it will echo back an upper-case S. Do not disconnect the programmer from the computer
after this point until the upgrade is complete.
- Now send the contents of the downloaded firmware upgrade file to the bootloader. The firmware upgrade
file is a plain-text (ASCII) file, so you can open it in a text editor (such as notepad), copy the whole thing,
and then paste it into your terminal program. Br@y terminal has a “Send File” button you can use. - While the file is being sent, the bootloader will send back period characters (“….”). This process will
take about 5 seconds. When the firmware upgrade is complete, the bootloader should send back a pipe
character (“|”) and turn the red LED on. - You can now unplug your programmer, plug it back into the computer, and use the new firmware.
If you run into problems during a firmware upgrade, please contact us [pololu.com/contact] for assistance.
My question is at this point can I undo what I have done and try to use the programmer with the “special modified firmware version” to flash the code onto my Arduino Uno?
I am getting so far in over my head here maybe I can find someone that could update my programmer and flash my Arduino with GRBL code so I could get to building and fabricating my desktop 3 axis gantry.
Sincerely,
Colin Morris