With respect to BDD's concern, the /OE of the EEPROM is tied to CPU pin 40. So shouldn't that mitigate the bus contention?
@Jeff, what should I look for to see if you concern has been handled?
@All, while trying to find parts on Mouser I noticed that the CY7C199CN is out of stock and obsolete. It looks like it will be hard. Not sure what to do about that, although I suppose I could use a regular width static RAM in an adapter.
Mousers results for the DS1813 contain a number of parts in the through hole format that differ slightly in part number. See
https://www.mouser.com/Search/Refine?Keyword=DS1813Usually when this happens there's something I don't know about part ordering.