TMS320F28379D: Cannot set threshold in comparator module

Imre Kiss1

Part Number: TMS320F28379D
Other Parts Discussed in Thread: CONTROLSUITE, LAUNCHXL-F28379D

I am running the code "controlSUITE\development_kits\TMDSIDDK_v2.0 \IDDK_PM_Servo_F2837x" on the

LAUNCHXL-F28379D

The subrouting void cmpssConfig(volatile struct CMPSS_REGS *v, Uint16 Hi, Uint16 Lo) is used to initialize the comparator modules 1 and 3. By inspection, all registers appear to initialize correctly except for the folwing:

v->DACHVALS.bit.DACVAL = Hi; // Set DAC-H to allowed MAX +ve current
v->DACLVALS.bit.DACVAL = Lo; // Set DAC-L to allowed MAX -ve current

No matter how I try to initialize these (I tried to hand code...), the same values appear in the registers namely

DACHVALA 0x0D55 CMPSS High DAC Value Active Register [Memory Mapped]

DACLVALS 0x02AA CMPSS Low DAC Value Shadow Register [Memory Mapped]

These values are appear irrespective of the values used for Hi and Lo.

thanks

over 7 years ago

0 Ramesh Ramamoorthy over 7 years ago

TI__Mastermind 27240 points

I am afraid if it has anything to do with compiler settings, or on the scope of the variable. It may need some minor work around. Try doing some dummy initialization in the main routine or somewhere else in the code before it is used here. Let me know if you resolve.

0 Imre Kiss1 over 7 years ago in reply to Ramesh Ramamoorthy

Intellectual 520 points

Thanks,

I will try your suggestion. It will be a few days. Kind of backed up.

0 Imre Kiss1 over 7 years ago in reply to Imre Kiss1

Intellectual 520 points

Thank you,

I found the problem. I was setting the thresholds in subroutine cmpssConfig. But the subroutine CMPSS_DIG_FILTER also seems to be executing and according to the comments, it is executing every 50ms by being called in subroutine A1(void). This must have been overwriting my settings. When I commented out the subroutine calls CMPSS_DIG_FILTER in A1, my settings behaved as expected.

Imre

0 Ramesh Ramamoorthy over 7 years ago in reply to Imre Kiss1

TI__Mastermind 27240 points

Glad you figured it out.

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TMS320F28379D: Cannot set threshold in comparator module