Hi Jeff
> With 5502 we're running 300 MHz and EMIF (SRAM)
at 100 MHz (I think, have
> to ask our engineers) and that seems to be stable. I wonder if the EMIF
> issues you mention also exist on 5510...
Ok I see.
Yes I am also wondering if 5510 has the same PLL design.
The strange thing is that what I am reporting is very basic and it must have
been observed by all.
Best Regards
Mitko
>
> -Jeff
>
>> My conclusions on the EMIF problems due to PLL instability:
>>
>> 1. The load on clockout pin influences the C5509A PLL stability
>> significantly in case clockout signal is enabled (in both EBSR and ST3_55
>> registers)!
>>
>> 2. In case clockout signal is disabled the load on clockout pin
doesn't
>> influence the PLL stability anymore.
>>
>> 3. The EMIF of C5509A is not stable (at CPU clock around 200 MHz ) unless
>> PLL_MULT is higer than 30.
>> In this case to get acceptable CPU rate the PLL_DIV should be 1 so we
>> have Fcpuystal*PLL_MULT/2 and for example for FcrystalMhz and
>> PLL_MULT1 I got Fcpu6Mhz. If I try to get the Fcpu around 200Mhz
>> using PLL_DIV=0 and smaller value of PLL_MULT the EMIF is unstable.
>>
>> My conclusion: Alyaws use PLL_MULT as big as possible if you need EMIF of
>> C5509A to work (at acceptable CPU speed).
>>
>> I will be very gratefully if someone tests the following code on his
>> hardware. Just replace LED_ON/LED_OFF with some code to control a LED on
>> your board. I think that that this loop will be stable only if the CPU is
>> running on very low frequency <50Mhz or if PLL_MULT is > 30 (and
>> therefore PLL_DIV=1).
>>
>> while(1){
>> asm("\tMOV #25,*(#0x20000)"); // Write to external memory
>>
>> LED_ON;
>>
>> asm("\tMOV #125,*(#0x20001)"); // Write to external memory
>>
>> LED_OF;
>> }
>>
>> Best Regards
>> Mitko
>> Andrej-
>>>
>>>Your answer is great -- that must have been some debug battle to figure
>>> it out. Just
>>>lab work, not in the docs, no obvious clues...
>>>
>>>It's gems like this that renew my faith in tech group collaboration.
I
>>> can give 20
>>>answers on the group, then to see one pop up like this is the reward.
>>> Thanks.
>>>
>>>-Jeff
>>>Andrej Novak wrote:
>>>
>>>> Hi Mitko,
>>>>
>>>> We had also hard time trying to make the 5509A working properly. We
>>>> have been using
>>>>
>>>> 5509 for 4 years on few different devices and now we have switched to
>>>> 5509A on all
>>>> devices. We are
>>>>
>>>> using PLL initialization procedures in usb uploader, bootloader and
>>>> firmware.
>>>>
>>>> The problem we had was the same as yours ? after some time the 5509A
>>>> stops working!
>>>> On 5509 this
>>>>
>>>> problem was not noticed.
>>>>
>>>> After several days of testing the conclusion was that the load on
>>>> clock out pin
>>>> could affect the processor stability.
>>>>
>>>> (on 5509 it was not possible to divide the system clk if the JTAG was
>>>> disconnected
>>>> - we have used hardware dividers).
>>>>
>>>> Our scheme characteristics (previous 5509A): clock out directly
>>>> connected to
>>>> 74lvc245 (Cl=4p; Rin=several Mohms.)
>>>>
>>>> After we have put a resistor in series (current version 5509A):
>>>> clockout ? resistor
>>>> 100R ? 74lvs245 the 5509a is working properly!
>>>>
>>>> Conclusion: Pay attention to clockout pin. Put in series a resistor.
>>>> Higher
>>>> resistance value will decrease the slopes
>>>>
>>>> (it depends also on your design ? Cload). Lower resistance could cause
>>>> the
>>>> malfunction of the PLL.
>>>>
>>>> Regards,
>>>>
>>>> Andrej Novak
>>>>
>>>> AGB Lab d.o.o.
>>>>
>>>> -----Original Message-----
>>>> From: c... [mailto:c...] On Behalf Of
>>>> d...@dsp-bg.info
>>>> Sent: Wednesday, June 21, 2006 9:41 AM
>>>> To: c...
>>>> Subject: [c55x] TMS320VC5509A EMIF problem (due to PLL unstability I
>>>> guess)???
>>>>
>>>> Hello All,
>>>> I have a very hard time trying to make the EMIF in TMS320VC5509APGE-4A
>>>> working stable at 192MHz.
>>>>
>>>> The test conditions:
>>>>
>>>> Hardware: DSP: TMS320VC5509APGE-4A
>>>> Vdd=3.3V, Vcore=1.6V
>>>> We have a supervisor which monitors Vdd, Vcore and manual reset button
>>>> Crystal: 12 MHz,
>>>> CPU works at 192 MHz
>>>> LEDs on: GPIO0 - Green,
>>>> GPIO1 - Red
>>>> ARDY pin is pulled up using 2.2K
>>>> On reset we put GPIO0=0, GPIO1=0, GPIO2=1, GPIO3=0
>>>>
>>>> 1. My initialization routine is:
>>>>
>>>> _c_int00: BSET ST1_INTM ; Init stack pointers
>>>> AMOV #(STACK+STACK_SIZE),XSP
>>>> AMOV #(SYSSTACK+STACK_SIZE),XSSP
>>>>
>>>> MOV #0000000000000111b,port(#0x07FD) ; SYSR (CLKOUT=CPU_CLK/14)
>>>> MOV #1000001000000001b,port(#0x6C00) ; EBSR (Full EMIF, CLKOUT
>>>> disabled)
>>>> MOV #0000000000000000b,port(#0x0001) ; ICR (All domains active)
>>>>
>>>> MOV #RESETIV > > 8,mmap(IVPD); Init interrupt table pointers
>>>> MOV #RESETIV > > 8,mmap(IVPH)
>>>>
>>>> MOV #0100100100000000b,mmap(ST1_55) ; Status registers
>>>> MOV #1111000000000000b,mmap(ST2_55)
>>>> MOV #0001110000000100b,mmap(ST3_55)
>>>>
>>>> MOV #00DFh,port(#3400h) ; GPIO - all outputs
>>>> MOV #0000h,port(#3401h)
>>>>
>>>> MOV #0x0810,port(#0x1C00) ; CLKMD
>>>> WAIT: BTST #0,port(#1C00h),TC1 ; Wait for PLL lock
>>>> BCC WAIT,!TC1
>>>>
>>>> EMIRST_CFG ; Initialize EMIF (192 MHz)
>>>> MOV #EMIRST_DATA,port(#EMIRST); Reset EMIF
>>>>
>>>> ; memfreq,wpe,memcen,nohold
>>>> EGCR_CFG MEMFREQ_1BY16X,WPE_OFF,MEMCEN_OFF,ARDYOFF_ON
>>>> MOV #EGCR_DATA,port(#EGCR) ; Global control register
>>>>
>>>> ; mtype,rdsetup,rdstrobe,rdhold
>>>> CEx1_CFG ASYNC16,1,8,2
>>>> ; rdexhld,wrexhld,wrsetup,wrstrobe,wrhold
>>>> CEx2_CFG 0,0,1,3,2
>>>> ; timeout
>>>> CEx3_CFG 96
>>>>
>>>> 2. The problematic loop
>>>>
>>>> void main()
>>>> {
>>>> while(1){
>>>> volatile ioport unsigned int *p;
>>>>
>>>> p = (volatile ioport unsigned int *)(0x3401);
>>>>
>>>> asm("\tMOV #25,*(#0x20000)"); // Write to external memory
>>>> *p |= 0x0002; // Red on
>>>> *p &= 0xFFFE; // Green off
>>>>
>>>> asm("\tMOV #125,*(#0x20001)"); // Write to external memory
>>>> *p &= 0xFFFD; // Red off
>>>> *p |= 0x0001; // Green on
>>>> }
>>>>
>>>> }
>>>>
>>>> In the loop above I write in the external memory and toggle the RED
>>>> and
>>>> GREEN LEDs.
>>>> After some time however (this time can be from 1sec up to several
>>>> hours) the LEDs stop toggling.
>>>> CE0 and AWR signals stop as well. It seems the program flow suddenly
>>>> goes outside the loop.
>>>>
>>>> If we put LED toggling in the timer1 interrupt it continue normally so
>>>> the DSP continue
>>>> working but ouside the loop.
>>>>
>>>> All maskable interrupts are disabled. I have tried to put several
>>>> NOPs in between of the instructions in the above loop but without any
>>>> improvement.
>>>> 0x20000 is just an example. The behavior is the same if other address
>>>> from the external space is used.
>>>>
>>>> The problem stays the same if we remove the external periferal which
>>>> we
>>>> have at 0x20000 location. Note that we can read and write correctly
>>>> from it. It is unstability problem.
>>>>
>>>> If internal address is used we don't observe this problem. I have
>>>> experimented changing the time
>>>> parameters of CE0 and AWR but again without success. I desperately
>>>> need
>>>> your help! Now I know almost
>>>> the same about this problem as I knew 10 days ago (when I faced it).
>>>>
>>>> I have a feeling taht this is some EMIF problem due to PLL
>>>> unstability?
>>>>
>>>> If you need more information just let me know. I can send you my test
>>>> project as well.
>>>> Kind Regards
>>>>
>>>> Mitko
>>>> ---------------
>>>> DSP forum from bulgaria
>>>> www.dsp-bg.info
>
Re: Re: TMS320VC5509A EMIF problem (due to PLL unstability I guess)???
Started by ●June 27, 2006
