nah thats cool mate, I really appreciate everybodys help.

Ive just fixed the 16 seconds to initialise problem. I put a 1meg resistor across the crystal and it initilises and locks instantly at switch on. Ive a 4mhz xtal with a 22pf to ground either side as i would normally use. I remove the resistor and it takes 16 seconds again. Any idea what is happening here?

and ive tried several different 4mhz xtals all with same results

I can't remember if you had the crystal on the PIC or the PLL, but in any case some ICs need a parallel high value resistor across the crystal for the clock to start properly.

Analyser wrote:I can't remember if you had the crystal on the PIC or the PLL, but in any case some ICs need a parallel high value resistor across the crystal for the clock to start properly.

For some strange reason I cant get it to work when I put the xtal connected to the Pic chip with a link to osc in on motorola. It only works if I put the crystal on the motorola chip with a link across to osc in on the pic chip

cheers analyser

radio-berlin wrote:

Analyser wrote:I can't remember if you had the crystal on the PIC or the PLL, but in any case some ICs need a parallel high value resistor across the crystal for the clock to start properly.

For some strange reason I cant get it to work when I put the xtal connected to the Pic chip with a link to osc in on motorola. It only works if I put the crystal on the motorola chip with a link across to osc in on the pic chip

cheers analyser

No worries. Does it really matter? I'm not sure the MC145 was designed to work with an external clock pulse but if you're experimenting you could try tying the unused pin of the PLL to ground via a 10nF/ 100nF decoupling cap and see if that works?

radio-berlin wrote: For some strange reason I cant get it to work when I put the xtal connected to the Pic chip with a link to osc in on motorola. It only works if I put the crystal on the motorola chip with a link across to osc in on the pic chip

From a quick web search, it seems that many have had issues with PIC crystal oscillators not oscillating - in similar scenarios, and without obvious explanation in the hardware or config, so I guess this may be the issue here.
In terms of the (now fixed) slow start of the Motorola oscillator, I guess either the overall feedback, or the phase of the feedback via the crystal, is marginal for oscillator startup, and the resistor is providing a little startup excitation ?

Cheers for all your help peeps