Mostek MK3850N-3, second-source F8 CPU.
Mostek MK3853P, second-source F8 SRAM interface.
Mostek MK3870/20, a conventional 3870 variant.
The MK38P70/02J is a rare development version of the MK3870, in a 40-pin purple-and-gold ceramic DIP with unusual underside pins and a piggyback socket. Variants which accept 24- or 28-pin EPROMs are available.
The 97400R variant pictured here is tooled for 24-pin EPROMs, and accepts 2516, 2532, 2716 and 2758 devices. We happen to have a purple-and-gold Mostek MK2716T, making for a very nice matched set.
The money shot. EPROMs like it on top.
Mostek MK38P70/02H, a variant which accepts 28-pin EPROMs.
Fairchild 3871EPC, second-source 3870 support chip.
