I was given a fairly large box of ICs, dating from the 1970s up to the 1990s. A lot of stuff that seems more or less computer related; Z80s, 6502s, and various support chips; 74HC TTLs in both PDIP and SOIC packages; PALs; 1980s 2114/4116/6116 RAMs; and so forth.
But these four really jumped out at me. I'm certainly no EE, but I've been inside way more than my share of electronics, and I've never seen anything quite like this.
![Identify these weird EPROMs 1705492-0](https://www.eevblog.com/forum/index.php?action=dlattach;topic=362611.0;attach=1705495;image)
Given the '82-'83 date codes, my best guess is that they're very early production 27256 EPROMs made from four 2764s glued together, with the PAL decoding the two extra address lines.
Anyone seen these before, or know the part number? Think they'd program as MBM27256s in my UniSite?