I wanted to follow-up and report my findings in case anyone else is having this problem.
First, I reached out to inventables.com technical support and they asked me to report any errors in the Firefox browser web developer’s console.
There were none.
Next they asked me to report if the driver is running by issuing the following command in the terminal:
$ ps aux | grep easel
The result showed the driver is running.
Next they asked me to report the Easel driver log files by entering the following command in the terminal:
$ cat /var/log/syslog | grep easel-driver
This output showed no errors from the easel driver.
Based upon this data they concluded that the Easel program is communicating with the Easel driver but not with my CNC machine.
They suggested that I try using another USB cable or reflashing the firmware on my CNC machine and making sure no other control software is running/interferring.
Next I went to the following website and downloaded the latest version of the grbl software for Arduino:
The version I downloaded is: grbl v1.1h (2019-08-25) Release
I started exploring how to flash the firmware on my CNC machine and found the following information on the Sainsmart Genmitsu CNC Users Group’s Facebook page:
“Hello Everybody! We received a few cases where users had updated their firmware to the latest version of GRBL and began to experience issues. We just want to remind folks to not update your machines firmware unless its supported by us (posted to our product page or wiki) as it will impact your machines performance and/or functionality. The 3018-PRO / PROver is shipped with GRBL 1.1F, if you attempt to flash GRBL 1.1H you will brick the offline controller. We have attached a guide for updating/reflashing your firmware in case you were affected or need to update your firmware with a build provided by us in the future.”
At this point I know my Sainsmart 3018 PROVer CNC machine has customized firmware (version 1.1F versus the 1.1h previously downloaded from github).
Still, I wanted to find out whether the grbl 1.1h version (from github) would work with the easel driver (even though my customized version would not).
I used the Arduino IDE to flash an Arduino Nano with grbl version 1.1h.
Next, I opened Firefox and the Easel program.
I clicked on Machine, and selected the same information in the dropdown boxes as in my original post.
When it asked me to plug in my CNC machine I plugged in the Arduino Nano that I previously flashed and the Easel driver was able to communicate with it without any apparent problems.
The Easel program and driver seem to work fine on my Linux desktop running Linux Mint ver: 19 Tara, xfce desktop, Firefox browser, easel driver supplied by inventables.com. This configuration communicates apparently without problems with an Arduino Nano with grbl-1.1h firmware. However grbl-1.1h will ‘brick’ my CNC’s offline controller and cause other “issues” for my CNC machine according to someone from SainSmart Technology, Inc. Therefore, I will forego using the Easel driver and instead download the gcode produced by Easel and then continue to use the Candle software (or Universal GCode Sender software) to control my CNC machine.