The only hint I see is on the connector on the right side. ("CSSIPC-P4A ...")
One "similar" item I could find was this: "CSSIPC-P4P", a PC104 board:
https://aliexpress.com/item/4001271479557.htmlBut your board doesn't look like a PC104 one. Probably another kind of industrial computer module. Found a couple other "CSSIPC" boards.
The only reference of manufacturer I could find with similar named boards are from a manufacturer apparently called "Eberle". Like this item:
https://www.ebay.de/itm/280578093276I suspect this is this company:
https://www.eberle.de/ , and those PC boards have long been obsolete with very little info to be found about them, so I can't be sure 100%.
The fact there are Siemens chips on the board would tend to lead us to this direction of a german company too.
There seems to be a sticker on the IC at the top of the first picture, which is hard to read. Maybe there's some info on it that could also help.