Question about the EQ slew in 1452

Hi,

I notice the EQ slew function from wiki, Current Coefficient = Current Coeffcient * a + Target Coeffcient * (1-a) .

I want to use the EQ slew in my program running on SHARC DSP to avoid the click noise when I change filter coefficients.

I wonder what the coefficient to slew is. If the coefficients are filter coefficients b2,b1,b0,a2,a1, when the coefficients slew to the target use this function, the filter based on the coefficients maybe become unstable, which will produce unexpectable outputs. So how the 1452 do the EQ slew, please give me some ideas.

Thanks.