gnu@sun.uucp (John Gilmore) (05/16/84)
They are two different things. The only similarity is that both come in pin-grid packages instead of DIPs. The 68012 is the same chip as the 68010. When they designed the 68010 they made more signals available on pads around the edge of the chip, but they wanted to keep it pin-compatible with the 68000, so they didn't connect them on the 64-pin DIP package. The 68012 has those pads connected, giving 7 more address lines (they left out A30 -- NOT A31 -- for good reasons) plus a pin that says whether a Read-Modify-Write cycle is in progress. I don't have the specs handy but I think those are the only new signals. The 68020 is a completely new chip (CMOS, 32 bit addr and data bus, runs much faster, etc). There was a report on Usenet that it has seen first silicon but I haven't seen any samples.