TMS320F2800157: TMS320F2800157: Timer Configuration

Mazen Hanafy

Tool/software:

Hello,

I am currently working with the cpu timers of the TMS320F2800157 controller. I am trying to make the configuration of the timers as configurable as possible. Therefore I created a struct that represents the config of one timer and put the values I needed in them such as TCR and TPR as the value of the whole registers and I made a const array of structs and I initialized the values that represents the value of the whole register using masking of all bits in the register. When I debug, I notice that the values of the array of structs are initialized correctly but when I assign them to the register value using for example ...TCR.all = (value of register) tha value doesn\t get set in the register. Why is that? Do I need to set the bits of the register timers bit by bit?

The following is an example of my code setting:

CpuTimer0Regs.TPR.all= Timer_Config_Array[TIMER2_INDEX].u32Tpr_R;

CpuTimer0Regs.TPRH.all = Timer_Config_Array[TIMER2_INDEX].u32Tprh_R;

CpuTimer0Regs.TCR.all = Timer_Config_Array[TIMER2_INDEX].u32Tcr_R;

CpuTimer0Regs.PRD.all = Timer_Config_Array[TIMER2_INDEX].u32Prd_R; /* set period value */

As I said the values in the struct members is correct, but they are not being set in the registers.

Note: i also tried EALLOW and EDIS when setting the registers but the values do not get set

over 1 year ago

0 Delaney Woodward over 1 year ago

TI__Mastermind 25250 points

Hello Mazen,

Usually when writing to a register field using the .all access, you want to OR equals instead of writing the whole register to isolate the field you are writing. In the case of the TPR and TPRH registers, only the TDDR field has read and write access, not the entire register. So, I would first suggest changing your writes to the following:

CpuTimer0Regs.TPR.all |= Timer_Config_Array[TIMER2_INDEX].u32Tpr_R;

CpuTimer0Regs.TPRH.all |= Timer_Config_Array[TIMER2_INDEX].u32Tprh_R;

CpuTimer0Regs.TCR.all |= Timer_Config_Array[TIMER2_INDEX].u32Tcr_R;

CpuTimer0Regs.PRD.all |= Timer_Config_Array[TIMER2_INDEX].u32Prd_R; /* set period value */

Could you try reading your struct value into variables instead of the register to verify that the struct accesses are being done correctly via the debugger?

I'm assuming these struct members are uint32_t type based on your naming convention. Note that the TPR, TPRH and TCR registers are 16-bit registers so these should be changed to uint16_t struct members to avoid error.

Best Regards,

Delaney

0 Mazen Hanafy over 1 year ago in reply to Delaney Woodward

Prodigy 20 points

Hello Delaney,

I've adjusted my code for the comments you have said to be done and this is the code right now:

volatile u16 u16Tpr_R = Timer_Config_Array[TIMER0_INDEX].u16Tpr_R;

volatile u16 u16Tprh_R = Timer_Config_Array[TIMER0_INDEX].u16Tprh_R;

volatile u16 u16Tcr_R = Timer_Config_Array[TIMER0_INDEX].u16Tcr_R;

volatile u32 u32Prd_R = Timer_Config_Array[TIMER0_INDEX].u32Prd_R;

volatile u32 u32PerfAct = Timer_Config_Array[TIMER0_INDEX].u32PerfAct;

volatile u32 u32PerfAvg = Timer_Config_Array[TIMER0_INDEX].u32PerfAvg;

volatile u32 u32PerfMax = Timer_Config_Array[TIMER0_INDEX].u32PerfMax;

volatile u32 u32PerfMin = Timer_Config_Array[TIMER0_INDEX].u32PerfMin;

volatile u16 u16PerfOvf = Timer_Config_Array[TIMER0_INDEX].u16PerfOvf;

EALLOW;

/* Set reset values for bootloader compitability */

CpuTimer0Regs.TPR.all |= u16Tpr_R;

CpuTimer0Regs.TPRH.all |= u16Tprh_R;

CpuTimer0Regs.TCR.all |= u16Tcr_R;

CpuTimer0Regs.PRD.all |= u32Prd_R; /* set period value */

EDIS;

When I debug, the values are placed in the volatile variables I have created correctly but at the |= assignments, the registers are not being written. Why is this? Does this mean that the registers of the timers cannot be written by the .all approach

0 Delaney Woodward over 1 year ago in reply to Mazen Hanafy

TI__Mastermind 25250 points

Hi Mazen,

No, it should be possible to write the CPUTIMER registers with the .all approach. Can you send me your code and I will try to replicate the issue?