P89c51rd2 (which model)

[raf]

Has anyone meets with uC phillips p89c51rd2bn? What model is this?
Is this one of the models p89c51rd2Hxx? Another question is about 6 clock and 12 clock mode. What settings is default? Can I simple change 6clock mode to standard for 8051 - 12? (if default is 6 - Must I set in Flash magic in section 4, 6clks/cycle?) And what about frequrency? For example: in 12clock mode is 11.0592.  In 6 clock mode is 11.0592 too, and that means that uC is twice quicker than uC in 12 clock mode? So the frequency is so to say 2x11.0592?

[Andy Ayre]

There are two Rx2 families. They are:

89C51Rx2Hxx - second generation
89C51Rx2xx - third generation

They are similar but operate differently in some respects.

The Rx2Hxx default to 6 clocks/cycle and have an OTP fuse to program them to 12 clocks/cycle with a parallel programmer ONLY.

The Rx2xx default to 12 clocks/cycle and can be programmed to 6 clocks/cycle using Flash Magic. After each full device erase they go back to 12 clocks/cycle.

You are correct about the frequency/speed. 6 clocks/cycle doubles the execution speed for the same crystal frequency.