TMS320F28377D: SPEED COMPARISON TEST PLEASE

I would have expected you would see a little faster toggling than that too. Can you share your PLL configuration? Are you writing your own or are you using our InitSysCtrl or InitSysPll functions?

You may also want to try using XCLKOUT to check the SYSCLK rate.

Whitney

Hi Whitney, thank you for your reply. I'm getting desperate getting my PLL to 200Mhz and my PORTS data rate above 1.15Mhz. At the moment I don't have much hair left. LOL. :)

I'm using the F28377D control card with Docking station ver R4.1 which is very old. I purchased these 2 from TI years ago. I checked the docking stations PDF and there is no XCLKOUT pin accessible so I can't test the CPU clock speed.

I'm not a C programmer therefore I'm setting the PLL in assembler. My code is below. If my code is wrong can you please supply me with a working assembler PLL setup for 200Mhz. Other people here have tested their F28377D at 200Mhz and their PORTA data rate is 18.5Mhz so it seems that my PLL is not setting up properly or my control card is faulty.

Here's my PLL setup code:

; SET SYSTEM CLOCK
			EALLOW									; ALLOW PROTECTED REGISTERS TO BE ACCESSED.
			MOVL XAR7,#CLKSRCCTL1	;CLKSRCCTL1 = 0
			MOVW AL,#0							; 0 INTERNAL CLOCK INTOSC2
			MOVW AH,#0
			MOVL *XAR7,ACC
			
			LC __DELAY_SHORT				; DELAY FOR PLL

			MOVL XAR7,#SYSPLLMULT	;SYSPLLMULT
			MOVW ACC,#40					;10 * 40 / 2 = 200Mhz 
			MOVL *XAR7,ACC

			MOVL XAR7,#SYSCLKDIVSEL
			MOVW ACC,#1						; / 2
			MOVL *XAR7,ACC

			MOVL XAR7,#SYSPLLCTL1	; ENABLE NEW CLOCK
			MOVW ACC,#3						; 3
			MOVL *XAR7,ACC
			
			LC __DELAY_SHORT
			LC __DELAY_SHORT
			LC __DELAY_SHORT

; PLL LOCK BIT IS LOCKED. VERIFIED.

Thanks again Whitney and waiting for your reply.

Peter

You can configure the pin muxing for GPIO73 to XCLKOUT. GPIO73 should be accessible on the docking station.

We don't have an existing assembly function for configuring the PLL currently. The "System Clock Setup" section in the device Technical Reference Manual goes into the steps for initializing the PLL, so you could write your own based on that. The values you're writing to the registers look good for 200MHz, but not following the recommended order of steps could be causing your problem.

Are you using the CCS Registers view to debug your code? Are you checking the clock configuration registers to make sure they are being updated as expected? Do you see the SYSPLLMULT getting cleared at any point?

Whitney

Hi Whitney, Thanks for the info.

I have a 1024x600 LCD connected to my F28377D and I've written code to read the PLL registers and print the value to the LCD.

This works fine. I haven't checked if the SYSPLLMULT is changing after it's set because the PLL LOCK bit is set. I'll checked it now and let you know.

Peter

Hi Whitney, I've setup the XCLKOUT pin73 on my F28377D and the INTOSC1 and INTOSC2 is clocking at 9.22Mhz on my scope.

I set CLKSRCCTL3 to 0 (PLLSYSCLK) and my scope read 0. I guess my PLL setup is wrong.

Can you give me a step by step line by line in C to correctly setup the PLL and I will translate it to Assembler.

If my PLL is not running then why does my F28377D run faster when I raise the PLL multiplier? Strange.

Peter

Glad you have the system clock running at 200MHz now. Is your code running from RAM or flash? If it's in flash, the flash wait states could be causing the code to execute slower than it would in RAM. If it's not already in RAM, can you try moving it there?

I don't suspect any issue with your board currently.

Whitney