> As other people have pointed out, a shift register ignores data until a
> clock comes along. But, not knowing these parts, I still don't understand
> how the device knows where the end of a byte or word is. A typical SPI
> device clocks data through a serial in parallel out shift register, then
> captures the data in a parallel latch on the trailing edge of -CS. Without
> that, it seems that you'd never know where to latch the data.

Sorry I wasn't clear. The Agilent devices do have a clock signal, but they
don't have a chip select.

Communications become active when the clock starts clocking. There is
some logic in the chip to ensure that the input is valid; if not, then
the chip goes into a state where it can get valid again.
--
D. Jay Newman           !
jay@sprucegrove.com     ! Xander: Giles, don't make cave-slayer unhappy.
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