Forums

Re: Succeeded in read but failed in write from HOST to DSP through HPI

Started by ling...@yahoo.com.cn July 24, 2007
Lingbo-
>> Which 55x DSP are you using?
>>
>> We always use multiplexed mode for HPI. However, for non-multiplexed mode
>> I think
>> you still need to connect HCNTL1, which is not in your list above. Both
>> HCNTL0 and
>> HCNTL1 have to be connected to allow access to four (4) possible HPI
>> registers:
>>
>> -HPIC
>> -HPIA
>> -HPID no autoincrement
>> -HPID autoincrement
>>
>> In the C5502 data sheet, Figure 3-5 shows both HCNTLx connected for
>> non-multiplexed
>> HPI. If you're not using 5502, then possibly look for a similar figure in
>> other 55x
>> data sheets.
>>
>> Also, do you have HPIENA active? What about pull-up/down Rs on GPIOx
>> lines that
>> select HPI mode at Reset?
>>
>> -Jeff
>>
>> Hi,Jeff,
>> I'm using 5510 v2.2,which is not supporting multiplexed mode for HPI anymore.In
>> non-multiplexed mode,HCNTL1 is used as HA1(ADDRESS 1).Only HCNTL0 is configured to
>> selecte the HPID/HPIC register.
>> There may be lots of differences between 5510 and 5502. I can not find any pin
>> named HPIENA.
>> DSP is powered up with BOOTM[3:0] = 1101,which selects the EHPI Boot Mode .Each
>> GPIO of these is pulled up/down by a 10K Rs.
>> Thank you for your email.
>
>Ok 5510 and not 5502. Then your hook-up may be Ok. Are you sure 10k is strong
>enough value for pull-up/down Rs? You might check the data sheet closely. Sometimes
>TI recommends stronger value, such as 1k.
>
>One debug suggestion -- read HPIC first. That's a known value, so it's easier to
>test. Then run some small DSP code (via JTAG) that sets HINT bit, and verify you can
>read the 1 bit change. If your HPI circuit doesn't allow you to read, then obviously
>you can't write.
>
>-Jeff
>
>PS. Please post to the group, not to me.
>
****************************************************************************
TI does not give a suggested value of RS to configurate the boot mode,just said"BOOTM[2:0] are sampled following reset to configure the boot
mode for the DSP."
Now,1K Resistors are used instead of 10Ks to pull up/down BOOTM[2:0].
And one change has happened that the internal memory can not be read anymore when the simulator is connected to the DSP.
Disconnecting the simulator, I can read the internal memory but not write as before.
-Ray