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hi! i am using the E128 ver with 16Mhz crystal oscillator and i wnated to know how can i increase my internal bus speed? and what is the maximum speed ?

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You can increase the internal bus speed by programming the PLL registers (SYNR and REFDV registers) and engaging the PLL (in the CLKSEL register). The maximum bus speed allowed is 25MHz (out of Reset your bus speed is 8MHz). The formula to calculate the bus speed when the PLL is engaged is: Fbus = Fextal * (SYNR + 1) / (REFDV + 1) You also need to make sure you have a network of two capacitors and a resistor available on the XFC pin. A PLL calculator to calculate the values can be found at: http://www.nohau.com/s12calc/pll_302.html Hope this helps, Doron Nohau Corporation HC12 In-Circuit Emulators www.nohau.com/emul12pc.html At 12:20 07/07/2004 +0000, you wrote: >hi! >i am using the E128 ver with 16Mhz crystal oscillator and i wnated to >know how can i increase my internal bus speed? and what is the >maximum speed ? [Non-text portions of this message have been removed]

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Discussion Groups | 68HC12 | speed

speed - koby_bens - Jul 7 7:20:00 2004

Re: speed - Doron Fael - Jul 7 8:01:00 2004