EDIS: Determine state of protected register access

Hi Clyde,

As far as I know, there is no possibility to see if the protected registers are "EALLOWED" or not. I think it is good practise to always squeeze the code that needs prot register access between EALLOW EDIS. I would have a very bad feeling invoking a function call with protected registers open...

BR Andreas

Hi Andreas,

I generally use good practices for writing code.  I am trying to find a solution to http://e2e.ti.com/support/microcontrollers/tms320c2000_32-bit_real-time_mcus/f/171/p/95623/334993.aspx#334993 ... one option is to disable the PWM by switching from EPWM1A to GPIO ... although I don't like that approach.  To be on the safe side, I'd want to view the state of the protected register before I take any action.

Clyde

Here is a way to retrieve the status of EALLOW.

//-----------------------------------------------------------------------------
void main(void)
{
  Uint16 uiEallowStatus;
  EALLOW;
  uiEallowStatus = gGetEallowStatus();
  EDIS;
  uiEallowStatus = gGetEallowStatus();
}
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
typedef struct {                                               
unsigned int SXM:1;       /* 0 Sign Extension Mode Bit 0 R/W*/                         
unsigned int OVM:1;       /* 1 Overflow Mode Bit 0 R/W*/                                
unsigned int TC:1;        /* 2 Test Control Bit 0 R/W*/                              
unsigned int C:1;         /* 3 Carry Bit 0 R/W*/                                    
unsigned int Z:1;         /* 4 Zero Condition Bit 0 R/W*/                           
unsigned int N:1;         /* 5 Negative Condition Bit 0 R/W*/                       
unsigned int V:1;         /* 6 Overflow Condition Bit 0 R/W*/                       
unsigned int PM:3;        /* 9:7 Product Shift Mode 0 (+1 shift) R/W*/               
unsigned int OVC_OVCU:6;  /* 15:10 ACC Overflow Counter 0 R/W*/
}ST0_Register;
//-----------------------------------------------------------------------------
typedef struct {                                               
unsigned int INTM:1;      /* 0 Interrupt Global Mask Bit 1 R/W*/                         
unsigned int DBGM:1;      /* 1 Debug Enable Mask Bit 1 R/W*/                                
unsigned int PAGE0:1;     /* 2 PAGE0 Addressing Mode Configuration Bit 0 R/W*/                              
unsigned int VMAP:1;      /* 3 Vector Map Bit 1 R/W*/                                    
unsigned int SPA:1;       /* 4 Stack Pointer Alignment Bit 0 R/W*/                           
unsigned int LOOP:1;      /* 5 Loop Instruction Status Bit 0 R*/                       
unsigned int EALLOW:1;    /* 6 Emulation Access Enable Bit 0 R/W*/                       
unsigned int IDLESTAT:1;  /* 7 IDLE Status Bit 0 R*/ 
unsigned int AMODE:1;     /* 8 Address Mode Bit 0 R/W*/
unsigned int OBJMODE:1;   /* 9 Object Compatibility Mode Bit 0 R/W*/
unsigned int rsvd1:1;     /* 10 reserved 0 R/W*/
unsigned int M0M1MAP:1;   /* 11 M0 And M1 Mapping Mode Bit 1 R/W*/
unsigned int XF:1;        /* 12 XF Status Bit 0 R/W*/
unsigned int ARP:3;       /* 15:13 Auxiliary Register Pointer 0 R/W*/
}ST1_Register;
//-----------------------------------------------------------------------------
ST0_Register ST0_REG;
ST1_Register ST1_REG;
//-----------------------------------------------------------------------------
unsigned int gGetEallowStatus(void)
{
  asm(" MOVW DP,#_ST0_REG");    
  asm(" PUSH ST0");
  asm(" POP @_ST0_REG");

  asm(" MOVW DP,#_ST1_REG");    
  asm(" PUSH ST1");
  asm(" POP @_ST1_REG");

  return ST1_REG.EALLOW;
}
//-----------------------------------------------------------------------------