Dear Jack,

I did not say that 68 series is variant of z80. I know they both are different.

I don't think comapnies like philips, Atmel, Dallas, Siemens, Winbond multi-buillion companies are mad to produce 8051 core microcontrollers. Which according to you is not at par of Z80 core.

Interestingly, some of the above companies have developed their finished products using 8051 core, means they just not produce the 8051 core based microcontrollers but they use this in their own products.

Anyway, I do not want to force you believing on us, but you must understand what other believes.

Rauf