PCI and ISA slot footprints? : rKiCad

What are these weird long ISA slots on this 386 board? isa slot pinout Figure 3 describes the pinouts for the full 16-bit ISA expansion slot, and Figure 4 shows how the additional pins are oriented in the expansion slot isa slot pinout All ISAEISA cards are backward-compatible, meaning if you have an 8-bit ISA expansion card, it will work in an 8-bit or 16-bit ISA slot, or the rearmost part

isa expansion slot pinout is proprietary to the motherboard vendor as well as POST cards The ISA-style bus cycles that were inherited by LPC from ISA are one-byte