Mystery chip SCM44506L

[Wouter de Waal]

>
>Very likely a semi custom or custom memory device, due to the prefix.

Armed with that and the fact that pin 1 connects to the leadframe I 
figured maybe it's something like the 6830 Mikbug prom -- 0V on 1, 5V 
on 12, data on the left, address on the right. Tried reading it like 
that (for all 16 combinations of chip selects) but 0xFF throughout.

So I popped the lid, stuck it under a microscope. The chip says 
"MCM6816" which is in fact a 1k ROM.

Anyone have more information on the 6816 ROM?

Thanks

W