Hello Andy Neil
your suggestion are corrects, i have visit and download all I find in Maxim Texas BB and others.
There are only applycations for a clock and somes external components, no whith normal 89C52.
Whith a chip integrate SPI i'ts very simple,
but i have available only a normal 89C52.
the 7843 are simylar to I2C, but the timing are differets, I have to keep duty from 40/60% and i'ts not easy whith C language.
My question is only if somebody have used, for take somes idea
regards
N.K.