Is there any way to access a high accuracy timer in Rabbit CPUs

Rabbit
1

…for instance, a register that is incremented once each clock cycle. All that I’m finding picking through the documentation is RTC’s, which I think don’t have the speed that I’m after. Ideally, there would something akin to the RDTSC instruction on x86.

2

Hi,

I am new to microprocessors and C in general (only done Basic in the past),

but I think I am after something similar. I want to use my Rabbit4000 with Pulse Width modulation to control the brightness of some LEDs to match the lunar cycle. So basically I would need to track the time and update the PWM duty cycle to be a smooth upward and downward curve such that it’s not ever constant.

I was thinking I could do this by writing an iterative function that sets the PWM duty cycle based on the current time (using a few if/thens to see if it should be dimming up or down, and determining the change in duty cycle using an exponential expresion). would this not work? or will it be plenty accurate since I am talking about slow gradual changes, whereas you are asking for something much more demanding???

sorry I don’t mean to distract from your original question, I’m just still feeling a bit lost is all :slight_smile:

Ryan

3

Is there any way to access a high accuracy timer in Rabbit CPUs for instance, a register that is incremented once each clock cycle. All that I’m finding picking through the documentation is RTC’s, which I think don’t have the speed that I’m after. Ideally, there would something akin to the RDTSC instruction on x86.

I would like to know this also.