TMS320F28377D: GSxMSEL access issue

Simen Biao

Expert 1875 points

Part Number: TMS320F28377D

Hi,

I used a variable( TestGs15) at CPU1 and located it in RAMGS15.

After execute "MemCfgRegs.GSxMSEL.all=0;" ,

TestGs15 can set the value directly if flash PREFETCH_EN set 0.

But When flash PREFETCH_EN set 1,

After execute "MemCfgRegs.GSxMSEL.all=0;"

TestGs15 should wait a cycle then set the value.

Could someone can explain why modify GSxMSEL should wait a cycle when REFETCH_EN set 1?

below picture , wait a cycle than can set value.

below picture , cannot set value directly.

best regards,

Simen

over 7 years ago

0 Vivek Singh over 7 years ago

TI__Guru** 116081 points

Simen,

Default value of MemCfgRegs.GSxMSEL.all is 0x0 only so updating this with value 0x0 should have no impact on access to GSRAM15. Since you are executing the code from flash, changing the PREFETCH_EN value will have some impact on execution cycle (based on the code alignment) hence you may see that variable is getting set after a cycle later while stepping through the code.

Regards,

Vivek Singh

0 Simen Biao over 7 years ago in reply to Vivek Singh

Expert 1875 points

Hi Vivek,

1. How to know that GSxMSEL should delay one cycle ? 2 cycles or more cycles?
2. Do you know any other registers like GSxMSEL should have delay after executing?
thanks,

best regards,
Simen

0 Vivek Singh over 7 years ago

TI__Guru** 116081 points

Simen, was this issue resolved?

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TMS320F28377D: GSxMSEL access issue