I am currently working on a project using the aduc848 controller and Keil uVision 2 and 3. We are attemping to make use of its PWM to simulate a 16 bit D/A signal to control a pressure regulator (0-5 volts). Currently, I am using a timer0 interrupt to increment the values in the PWM control register, but am having some difficulty in the timing needed for a full 0-5 volt ramp in a short period of time (~5 seconds). I was wondering if i am going about this ramping in the right way. If I am, is a resolution reduction necessary, or is there another way around calling the interrupt every time I need an increment. I am also making use of the chip's onboard A/D converter, and need to set up some sort of real- time clock for data acquisition purposes, and my concern is having too many interrupts being called too often. If you have any advice or suggestions, they'd be greatly appreciated.

Thanks,
Ryan Killian