• Too little to begin, too much to give up

    Tawez • 2 days ago • 0 comments

    There is really not so much about this chip. So far I've found just one tiny information on page 431 of the May issue of "Electronics World + Wireless World" from 1992 (PDF).

    In general LH72001 is the V20 core from NEC, a usual set of chips present on the PC XT main board like DMA, interrupt controller, timer, and other. In addition there are included keyboard controller, printer interface and glue logic between the chip and ROM/RAM.

    I've found by accident the PDF with the new product information that includes block diagram, pinout, pin description and electrical characteristics but nothing more, no timing details, no registers map.

    I also have 20 pieces of this chip, which seems to be enough to start with, without worrying about losing research material.

    What I don't have at the moment is the logic analyser with the decent amount of channels. 8 or 16 channels seems to be not enough to make a progress without wandering.

    If anyone want to help or want to do his own research, I can share the chips.