What is the difference between PL-501v1 and PL-501v2, and can I connect them together?

The difference is PL-501v2 is using INT6300, PL-501v1 is INT6000, and there are Reset and Security buttons on the bottoms panel of PL-501v2.
At the mean time, PL-501v1 need to use the utility version v3041B or above to upgrade firmware to v2 version, so that PL-501v1 and PL-501v2 can communicate with each other. Please link to http://www.planet.com.tw/download.php to download PL-501’s firmware.