Tool/software: Code Composer Studio
I am interested in the TIDM-BPM device for blood pressure monitoring and I checked out the source code provided on the webiste. I was especially checking the pwm signals for the pump and valve. Here is the part of the code concerned :
P1SEL|=BIT2+BIT3; //SELECT P1.2/P1.3 AS TA0 OUTPUT
TA0CCR0 = 4000; //
TA0CCTL1 = OUTMOD_7; // CCR1 toggle/set,PUMP
TA0CCTL2 = OUTMOD_1; //VALVE
TA0CCR2 = 3400; // CCR1 PWM duty cycle for valve
TA0CCR1 = HIGH_AIRIN; // for pump with HIGH_AIRIN = 2500
TA0CTL = TASSEL_2 + TACLR+ MC_1; // SMCLK, up mode,
My question is about the duty cycle of these two pwm signals. How the duty cycle of these pwm signals was determined compared to the inflation and deflation speed ? In other words what's the relationship used between the duty cycle and the inflation speed (for pump) and deflation speed (for valve). I mean let's say we want to reach a certain pressure of 200 mmHg in 20 s. How should we determine the duty cycle of the pump to reach this pressure in 20s ? I hope that my question is clear.
Thank you very much.