Texas DSP 2812 and McBSP

Digital Signal Processing

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Texas DSP 2812 and McBSP

Postby Torgeir Jakobsen » Thu, 02 Dec 2004 02:40:47 GMT

Hi all DSP experts :-)

I have a problem with the McBSP receive interrupt on the 2812 DSP from
Texas. Do anyone have working code on this DSP ?
I have done much the same as on the 5510 DSP where I did not have this
problem, so I do not understand why it is not working here ?

Thanks in advance.


Re: Texas DSP 2812 and McBSP

Postby Brad Griffis » Thu, 02 Dec 2004 10:44:32 GMT

There are more things you need to enable to get interrupts on the 2812 than 
there are on the 5510.  Are you sure that you have enabled the PIE, set the 
proper bit in the PIEIER for the McBSP interrupt, acknowledged the PIE 
(PIEACK), set the corresponding IER bit, and cleared the INTM bit?

Also, are you sure that you have configured the McBSP to generate a receive 
interrupt?  Are you seeing the RRDY flag which indicates there is data in 
the McBSP to be read?


Re: Texas DSP 2812 and McBSP

Postby Torgeir Jakobsen » Thu, 02 Dec 2004 18:55:30 GMT

Thank you Brad,

I have done the things you describe:
- Enabled PIE
- Set PIEIER for McBSP receive interrupt
- Acknowledged the PIE
- Set IER
- Cleared INTM.

First it looked like RRDY was not set, but now the RRDY is set. I have also
enabled the transmit interrupt to see if this was working better.  I can see
that RRDY and XRDY is set but the PIEIFR register (and PIEACK) does not flag
any interrupt, even if McBSP is set to generate interrupt on RRDY and XRDY
and the PIEIER is set to enable both interrupts.
I am using the sample rate generator, and the clock and frame signals are
generated correctly (measured with oscilloscope).

Any suggestions ?


Similar Threads:

1.McBSP interrupts on Texas 2812

I have problems with the receive and transmit interrupts on this DSP. I have
set the McBSP to generate interrupts on RRDY and XRDY, and I can see that
these bits are set when I emulate the program on my hardware (using XDS510PP
Plus and CCS). This should also have activated the corresponding interrupt
flags in the PIEIFR6 regsiter (bit 5 and 6), but this does not happen.
I can see that my ISRs are working if I set the interrupt flags in PIEIFR6
manually, so the problem is the connection between the McBSP and the PIEIFR6
register. What do I have to do to make the McBSP RRDY and XRDY activate the
flags in PIEIFR6 ?
I use the internal sample rate generator, and I can see the frame and clock
signals with my oscilloscope.

Thank you in advance.

2.hwo to set up interrupt in dsp 2812

Hi everyone!
I am new in using dsp 2812.

I want to make an T3PINT interrupt.

I just read "TMS320x281x DSP System Control and Interrupts Reference
Guide"(spru078e) and
"TMS320x281x DSP Event Manager (EV) Reference Guide"(spru065e),

On page 84 in spru065e,and on page 122 in spru078e,
what's mentioned in the priority field seems different.

I am traceing the C of the example "sw_prioritized_interrupts"
mentioned in the document "C281x C/C++ Header Files and Peripheral

It seems that cpu branchs to ISR to setup priority.Is this the way it
does? Or Is my understanding wrong?
(FILE:   DSP281x_SWPiroritizedPieVect.c)

If priority can be set in code,why priority are mentioned in these

Dose someone know how to accomplish this task?

Thanks a lot for your answers

3.own api flashing dsp 2812

I work on  a 2812 dsp board, I make a c# application to test it and now 
want to flash it.

On this board i have four Dsp (not interconnected), i use SDFlash wit
four com port and four sdp project.

I can create a process which will launch four SDFlash.
Does SdFlash can take arguments in a command line, like this ?
\SdFlash clientprjCom1.sdp
\SdFlash clientprjCom4.sdp

An other idea is to create my own window working like SDFlash.
In this case, do you know if it's possible to have SDFlash source code
or informations about c++ input methods that i can call to flash dsp.

A last question, does it exist an industrial method to flash more fastly
several dsp.

thank you for your help.

4.ADC's noise on DSP 2812

Hi everybody !!!

Can someone help me to solve the following problem ?
I need to use an external signal in my program in order to make a goo
enslavment of a signal.
So what, i want to get a very accurate value of my external signal.
I use the ADC module of the DSP 2812 but when I look a the value returne
there's a lot of noise on it.
Can someone explain me why this measure is so noisy and how i coul
improve it ?
Thanks a lot


5.DSP-2812: Calling SCI_BOOT from the program

Hi All,

I want to call SCI_BOOT in my program in order to use SDFlash to update
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flash and I don't want to change that. Or can the DSP-resetted in such
a way that it ignores the hardware and boots from SCI_BOOT anyway.

Kind regards, Frank

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