Firmware Switch & Update Instruction (Mac)You can now update the original firmware version and also switch from original firmware to grbl firmware with the latest mobile phone application. But if you need to switch back to the original firmware from the grbl firmware, you would still need to use a PC and follow the video instruction. When flashing the firmware, if you get this error message followed by no device found, but the device is actually connected and showing in the device manager.Watch Videos