[cctalk] Re: 7485 chip history??? (Solid State Music SB-1)

Hi, I recently acquired a Solid State Music SB-1 from which all the chips had been removed. I've reinstalled all of the chips (I located an SSM2000) and I've been trying to figure out why this board crashes my computers. The conclusion that I've come to is rather astounding. The board specifies two 74ls85 4 bit binary comparator chips to perform address decoding. The designers of this board seem to have had incorrect pinouts for it. Every source that I can find specifies: B3 1 16 VCC A<B (in) 2 15 A3 A=B (in) 3 14 B2 A>B (in) 4 13 A2 A>B (out) 5 12 A1 A=B (out) 6 11 B1 A<B (out) 7 10 A0 GND 8 9 B0 The 7485s that I was able to get have this pinout. BUT! The SB-1 is designed as: B2 1 16 VCC A2 2 15 A3 A=B (out) 3 14 B3 A>B (in) 4 13 A>B (out) A<B (in) 5 12 A<B (out) A=B (in) 6 11 B0 A1 7 10 A0 GND 8 9 B1 I Ohm'd out the board to verify this and it matches the schematic here: https://wiki.theretrowagon.com/wiki/Solid_State_Music_SB1 What the heck??? Did the pinout of the 7485 just arbitrarily change at some point? Was this some competition between manufacturers? Is there any way to get the "right" 7485? Thanks, Bill