Center Aligned Output PWM MPC5606B

duanemattern — Thu, 22 Sep 2016 19:57:11 GMT

I'm trying to use the Center Alignement Output PWM (OPWMCB) mode on the MPC5606B using the TRK-MPC4606B board. I'm using Codewarrior for MCU (V10.6) and I've already got the edge aligned PWM working for two channels. Now I'm trying to figure out the center align mode. I followed the guidelines in the MPC5606BRM.pdf document (27.4.4.1.1.10) and I'm using the CounterBus_A (emios_ch23) in up/down mode. But I'm not getting any toggle on the pins, so I'm trying to troubleshoot the setup. Here's the bulk of the setup that I'm using (which changed from the edlge-aligned). Any help would be appreciated. I started with some of the kit demo code and the board is running with CAN and RS232, GPIO, and the pushbuttons, LEDs, potentiometer, and photosensor on the board. It's just the center aligned PWM that I'm having difficulties setting up. Goal is a 100kHz signal with a 50% duty cycle based on a 16MHz clock., which I had working in the edge align version of the PWM (OPWMB).

/* EMIOS Module Configuration Register (EMIOS_MCR) */
EMIOS_0.MCR.R = 0x00000000; //disable

    /*   Unified Channel 23 Register                               */
   EMIOS_0.CH[23].CCR.R = 0x00000000;   //reset

   // MCB = Modulus Counter Buffered time base for the OPWMCB
   EMIOS_0.CH[23].CCR.B.UCPEN = 0;       // 2. Disable Channel Prescaler;
       EMIOS_0.CH[23].CCNTR.R = 1;        // 3. Write 0x1 at internal counter;
       EMIOS_0.CH[23].CADR.R = 81;        // 4. Set A register, period=2*(A-1)=160counts on 16MHz clock for 10us
       EMIOS_0.CH[23].CCR.B.MODE = 0x54; // 5. Set ch to MCB Up mode, 0x101-0100, internal clock, B1 not used
       EMIOS_0.CH[23].CCR.B.UCPRE = 0;    // 6. Set prescaler ratio to "1".
   EMIOS_0.CH[23].CCR.B.UCPEN = 1;       // 7. Enable Channel Prescaler

    /*   Unified Channel 24 Register                               */
   // OPWMCB [channel 1] output PWM center-aligned, buffered
   EMIOS_0.CH[24].CCR.B.UCPEN = 0;       // 8. Disable Channel Prescaler;
       EMIOS_0.CH[24].CADR.R = 41;      // 9. Set A register; (162-(162*%/100) )/2
       EMIOS_0.CH[24].CBDR.R = 0;       // 10 Set B register, deadtime = 0
       EMIOS_0.CH[24].CCR.B.BSL = 0;      // 11 Select time base (MCB modulus counter bus) = ALL channels,

                                          //   emios_0.ch[23]
       EMIOS_0.CH[24].CCR.B.EDPOL = 1;    // sets output with "A" match
       EMIOS_0.CH[24].CCR.B.MODE = 0x5C; // 12 Enter OPWMCB mode, center aligned,

                                           // output PWM, modulation buffered, trailing edge deadtime (not used)
       EMIOS_0.CH[24].CCR.B.UCPRE = 0;    // 13 Set prescaler ratio = 1
   EMIOS_0.CH[24].CCR.B.UCPEN = 1;       // 14 Enable Channel Prescaler;

EMIOS_0.MCR.R = 0x14000000;   // enable, start All channels at once

Re: Center Aligned Output PWM MPC5606B

duanemattern — Thu, 22 Sep 2016 20:10:19 GMT

I forgot to mention I have the emois [24] on PortE11 setup for alternate function 1 for this output, which is what it was set to for the edge aligned PWM which worked properly.

Re: Center Aligned Output PWM MPC5606B

PetrS — Mon, 26 Sep 2016 06:15:48 GMT

Hi,

The configuration looks correct, but on wrong channel. There is no OPWMCB mode on channel 24.

See Figure 24-7 of the MPC5606BRM , which shows the channel configuration of the eMIOS blocks.

Try the same on channels 1 to 7.

BR, Petr

MPC5xxxのトピックRe: Center Aligned Output PWM MPC5606B

Center Aligned Output PWM MPC5606B

Re: Center Aligned Output PWM MPC5606B

Re: Center Aligned Output PWM MPC5606B