topic Using ETC as input capture to measure pulse period between rising edges of measurement pulse. in S12 / MagniV Microcontrollers

Using ETC as input capture to measure pulse period between rising edges of measurement pulse.

KY — Thu, 28 Sep 2006 14:23:02 GMT

how can I do it?I have made some process,but it can't go to the interrupt process.Such as:

#pragma LINK_INFO DERIVATIVE "SampleS12"
#pragma CODE_SEG DEFAULT

void TIM_Init(void)
{
TIOS_IOS0 = 0;
TFLG1 = 1;
TIE_C0I =1;
TCTL4_EDG0A = 1;
TCTL4_EDG0B = 0;
ICOVW_NOVW0 = 1;
ICSYS_BUFEN = 1;
ICSYS_LATQ = 0;
ICSYS_TFMOD = 1;
TSCR1_TEN = 1;
}

#pragma CODE_SEG __NEAR_SEG NON_BANKED

/* Interrupt section for this module. Placement will be in NON_BANKED area.*/
interrupt 8 void TI0_Interrupt(void)
{

TFLG1 = 1; // Reset interrupt request flag

}

#pragma CODE_SEG DEFAULT

Re: Using ETC as input capture to measure pulse period between rising edges of measurement pulse.

DanielM — Mon, 16 Oct 2006 14:01:37 GMT

Hi,

have a look at

http://www.freescale.com/files/microcontrollers/doc/app_note/AN3292.pdf

and the associated code

http://www.freescale.com/webapp/sps/download/license.jsp?colCode=AN3292SW&prodCode=MC9S12XDP512&nodeId=0162468636bJwn1972&location=psp

This appnote uses the ECT to capture edges of the input signal and then uses the time between the edges to determine how many bits were "received" on an emulated SCI channel. You should be able to use almost identical ECT set-up for what you waht to do.

Daniel