What language or script please?

[cannonmn]

Thanks for all of the information. I was somehow hoping the inscription (above the letter "R") would have some kind of date information in it, but apparently not.

In any case, the cannon was represented to me as having come from a particular place in Mexico. I find it very hard to believe, given the presence of Arabic characters, that it really did come from Mexico. The only small bronze cannons I've seen in the U.S. with such Arabic characters have come from either the Philippines or Indonesia. It is possible but I think very unlikely that the cannon was cast and probably used in, say, the Philippines where it got the Arabic characters, then transported all the way to Mexico where it was supposedly used at a presidio.

Dom demonstrated to me how much more legible an inverted image can be, so I've inverted the image of this inscription in case anyone wants a better look at it.