Initial DAC MC56F8037

[repairDV]

Good day! Is the example of assembler code initial DAC in dsc MC56F8037?

[repairDV]

Good day! What is not normally in this code:

void initDAC0()

{

asm (move.w #$f08f,X:PIT0_MOD);

asm (move.w #08ff,X:PIT0_CNTR);

asm (move.w #$000f,X:PIT0_CTRL);

  asm (bfset #$1000,X:SIM_PCE1);

asm (move.w #$033e,X:DAC0_MAXVAL);

  asm (move.w #$f03f,X:DAC0_CTRL);

  asm (move.w #$000e,X:DAC0_DATA);

asm (move.w #$0f3e,X:DAC0_STEP);

asm (move.w #$003e,X:DAC0_MINVAL);

}

?

[xiangjun_rong]

Hi, Constantin,

I think your assembly code is okay to assign a constant to a peripheral register with move.w instruction.

The assembly instruction is described in DSP56F800ERM, pls download it from the website:

MC56F84xxx|Digital Signal Controllers|NXP

BR

XiangJun Rong

[repairDV]

Good day!

#pragma interrupt called

void initLED()

{

//---------GpioD

  asm(bfclr #$0030,X:GPIOD_PEREN); //#$0000  0000 0000 0011 0000

  asm(bfset #$0030,X:GPIOD_DDIR);

  asm (bfclr #$0010,X:GPIOD_DATA);

}

void initIsr ()

{

asm (bfclr #$FFFF,X:SIM_IPS1);

asm(bfset #$00c0,X:GPIOD_PEREN); //DAC0, DAC1 0000 0000 1100 0000

}

[xiangjun_rong]

Hi, Constantin,

I think your assembly code is correct to configure the GPIO pin and the DAC output pins. Regarding the line "#pragma interrupt called", if the api function is called in an ISR(Interrupt Service Routine), you have to add  the line "#pragma interrupt called" before the api function, which will push/pop all the registers the api function uses. If you define the ISR, you have to add "#pragma interrupt on" before the ISR so that the compiler generates the code to push/pop both PC and SR. For your case, it is unnecessary to add "#pragma interrupt called" before initLED() api function.

Hope it can help you.

BR

Xiangjun Rong

[johnlwinters]

Hi, Using CW 8.3 for DSC, I generated a project using Processor Expert Stationery.

I then added the DAC, with the default, for PE, settings.

Here is both the C code and its assembly equivalent generated to initialize the DAC for the 8037 device:

  setReg16(DAC0_CTRL, 0x01U);          

P:00000105: E418F1C00000        move.l   #0xf1c0,R0

P:00000108: 86400001            move.w   #1,X:(R0)

  /* DAC0_DATA: DATA=0 */

  setReg16(DAC0_DATA, 0x00U);          

P:0000010A: E418F1C10000        move.l   #0xf1c1,R0

P:0000010D: 86400000            move.w   #0,X:(R0)

  /* DAC0_MAXVAL: MAXVAL=0 */

  setReg16(DAC0_MAXVAL, 0x00U);        

P:0000010F: E418F1C40000        move.l   #0xf1c4,R0

P:00000112: 86400000            move.w   #0,X:(R0)

  /* DAC0_MINVAL: MINVAL=0 */

  setReg16(DAC0_MINVAL, 0x00U);        

P:00000114: E418F1C30000        move.l   #0xf1c3,R0

P:00000117: 86400000            move.w   #0,X:(R0)

  /* DAC0_STEP: STEP=0 */

  setReg16(DAC0_STEP, 0x00U);          

P:00000119: E418F1C20000        move.l   #0xf1c2,R0

P:0000011C: 86400000            move.w   #0,X:(R0)

  /* DAC0_CTRL: PDN=0 */

  clrReg16Bits(DAC0_CTRL, 0x01U);      

P:0000011E: E418F1C00000        move.l   #0xf1c0,R0

P:00000121: 80400001            bfclr    #1,X:(R0)

[xiangjun_rong]

Hi, Constantin,

Unfortunately, I have not the DAC code with assembly language and based on MC56F8037, but I have the code with PE based on MC56F82748, the DAC IP is similar for MC56F8023 and MC56F82748.

Hope it can help you.

BR

XiangJun Rong