What kind of IC is this

Hi, My Zilog S8000 Winchester Controller board carries 2 ceramic DIL16 packaged chips labeled (beside a logo) just with the two lines of text. The chip looks like this (tried to ASCII-art the logo in front of the text) +----------------------------------------+ | +-------+ | | |----- | | \ | > ----| 6306-1J | / |----- | 8147 | | | > ----| | | +-------+ | +----------------------------------------+ I guess the 2nd line means: 81 == 1981 47 == calendar week 47 So I wonder what 6306-1J stands for? I've not analyzed the circuit to see if it is a PROM or something like that. It is put in a socket so I guess it must be something (onetime?) programmable... Maybe you can tell... -- Oliver Lehmann http://www.pofo.de/ http://wishlist.ans-netz.de/