About the access timing from CPU when ELP sets ON with Auto mode

Hi,

The CPU will have to wake up the chip from ELP and then send data during ELP mode.
You can check the implementation in wl1271_ps_elp_wakeup() for more details. As you can see, the wakeup command is also send via SDIO.

Regards,
Gigi Joseph.

Hi Gigi,

Thank you very much for answering. But, I'm still a bit confused.

It is beacuse, as far as I did read WiLink6 Programmer's Guide, which said that,  "In ELP mode, all the active logic (SDIO, MAC, PHY, RF AFE Control) and analog blocks (radio, analog supply) in the WLAN IP are shut off. A small portion remains active to support wake-up."

Despite SDIO included all logics is shut off during ELP active, I don't understand why CPU can access via SDIO.

If I could understand this mechanism, I will be able to understand what you answered.

Best regards,

Satoh

Hi Satoh,

During ELP, only a small portion is available for the host.You can consider that only the HW_ACCESS_ELP_CTRL_REG_ADDR register is available for the host. This is what is used to wake up the device.

Regards,
Gigi Joseph.

Hi Gigi,

Thank you very much. I understood that HW_ACCESS_ELP_CTRL_REG_ADDR register was used to wake up the device.

I have one more question. DOes it mean that  CPU can always accsess to this register via SDIO with ELP/ON? And, WiLink8 also?

Best regards,

Satoh 

Hi Satoh,

Yes, and Yes.

Regards,
Gigi Joseph.