Old but Occaisionally Inconsistent

I have to work with PLC5's a lot and I went on autopilot addressing a bunch of them and could not make one work. After sniffing the serial stream I found it, and then found out why. Maybe this is well known but it caught me by surprise.

These 2 Nearly identical PLC 5/12's Node ID default number type is different. One defaults to Octal, like the other 30 do, but just this one defaults to decimal.

Change for the sake of... ? What

Someone decided that their way was better.

I'm confident that Operaghost is going to have the answer to this one. He posted something on the topic a couple of months ago.

The PLC-5/12 is a Classic PLC-5, right ?

And those screenshots are from RSLogix 5, of course.

It might have to do with whether you browsed to it with RSWho, or opened an old copy of the program to go online....

OG's gonna know.

I read all the old files with the same logix copy to gather the addresses for a comm project. So odd that the dialog can be changed by a firmware version like that.