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F28M35H22C: where is PDA bit in CAN ES register

Ben Qin
Intellectual 2690 points

Part Number: F28M35H22C

Hi Team,

I see there have description for PDA bit in CAN ES register, but I don't see PDA bit in CAN ES register.

Could you tell me where is the PDA bit?

Thanks & Regards,

Ben

  • 0
    TI__Guru* 95315 points

    Ben,

           The powerdown feature is Reserved. It was removed from the DCAN chapter of all newer devices but it was not done for F28M35H22C. 

  • 0 in reply to Hareesh Janakiraman
    TI__Intellectual 2690 points

    Hi Hareesh,

    Customer wants to make sure: for the newer F28M35x products, DCAN does not have powerdown and wakeup functions? Are the WUBA/PDR bits in the CAN CTL register and the WakeUpPnd/PDA bits in the CAN ES register reserved bits? 

    However, we use the F28M35H22C product, does it have powerdown and wake up functions? I still want to ask, which one is the corresponding PDA bit?

    In addition, for the global low power consumption mode, is it still available in the old F28M35x products and deleted in the new products? 

    Best Regards,

    Ben

  • 0 in reply to Ben Qin
    TI__Guru* 95315 points
    Ben Qin said:
    for the newer F28M35x products, DCAN does not have powerdown and wakeup functions?

    It is not about "newer" or "older". Nothing was changed in the silicon.

    Ben Qin said:
    Are the WUBA/PDR bits in the CAN CTL register and the WakeUpPnd/PDA bits in the CAN ES register reserved bits? 

    Yes.

    Ben Qin said:
    However, we use the F28M35H22C product, does it have powerdown and wake up functions? I

    The local-Powerdown feature of the DCAN module is not useful, since the power-saving realized is negligible. You may save 1 or 2 mA out of a total device current of 300 mA or more. 

    Ben Qin said:
    In addition, for the global low power consumption mode, is it still available in the old F28M35x products and deleted in the new products? 

    If you are referring to the SLEEP IDLE, SLEEP STANDBY etc, they are very much available. Nothing was deleted in any version of the silicon.

  • 0 in reply to Hareesh Janakiraman
    TI__Intellectual 2690 points

    Hi Hareesh,

    Thanks for you reply.

    The customer needs to confirm again in order to avoid the problem of inconsistency between the chip and the manual.

    According to the reply:

    1. The DCAN module in F28M35x, whether it is a new product or an old product, the WUBA/PDR bit in the CAN CTL register and the WakeUpPnd/PDA bit in the CAN ES register in the chip are reserved bits, so you don’t need to care about the description in the manual ,is that so?

    2. Does the DCAN module in F28M35x, whether it is a new product or an old product, always have the functions of Global Power-down Mode (SLEEP/DEEP SLEEP) and Wakeup from Global Power-down Mode? Which register in DCAN is this related to? If there are Global Power-down Mode and Wakeup from Global Power-down Mode functions, since the previous reply said that the WakeUpPnd bit is a reserved bit, why does the manual mention that the CAN ES register WakeUpPnd bit can be observed in Wakeup from Global Power-down Mode?

    Thanks & Regards,

    Ben

  • 0 in reply to Ben Qin
    TI__Guru* 95315 points
    Ben Qin said:
    1. The DCAN module in F28M35x, whether it is a new product or an old product, the WUBA/PDR bit in the CAN CTL register and the WakeUpPnd/PDA bit in the CAN ES register in the chip are reserved bits, so you don’t need to care about the description in the manual ,is that so?

    Correct.

    Ben Qin said:
    2. Does the DCAN module in F28M35x, whether it is a new product or an old product, always have the functions of Global Power-down Mode (SLEEP/DEEP SLEEP) and Wakeup from Global Power-down Mode?

    Yes, the SLEEP states are applicable to the whole device, not just the CAN module.

    Ben Qin said:
    Which register in DCAN is this related to?

    These states are not related to DCAN.

    Ben Qin said:
    If there are Global Power-down Mode and Wakeup from Global Power-down Mode functions, since the previous reply said that the WakeUpPnd bit is a reserved bit, why does the manual mention that the CAN ES register WakeUpPnd bit can be observed in Wakeup from Global Power-down Mode?

    As already mentioned, the local powerdown mode of DCAN module is not useful, since it does not result in any appreciable saving in current. Hence the local powerdowm mode was made Reserved.