TD Systems TDL-11 QBUS (SCSI?) card

Eric Smith spacewar at
Sun May 3 23:41:46 CDT 2015

On Sun, May 3, 2015 at 10:08 AM, Sean Caron <scaron at> wrote:
> That this one turned out to be SCSI with the strange Z8400 CPU

What's strange about a Z8400? That's a normal Z80 CPU. If there are
two additional digits after "8400", that's the rated speed in MHz, as
opposed to the older alpha scheme (Z80 = 2.5 MHz, Z80A = 4 MHz, Z80B =
6 MHz, Z80H = 8 MHz).

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