PMU issue (CYW4343w)

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IlBy_4632306
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Hi, I use SP-KL1DX-T chip with  Cypress/CYW4343W IC.(linux 4.1.15). Firmware - cyw-bt-patch/CYW43430A1.1DX.hcd at master · murata-wireless/cyw-bt-patch · GitHub

WLAN and Bluetooth work fine but I want to try PMU features.

I read your datasheet(https://www.cypress.com/file/298081/download) page 27 and I decided to use BT_HOST_WAKE.

Where I can find information about ' power management handshaking' ?

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VinayakS_26
Moderator
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Hi IlBy_4632306

By power managment handshaking refers to the signalling between host and device to leverage the power management features provided by CYW4343W.

Following is the Required Host Side Implementations.

 Configure interrupt source to be triggered by BT_HOST_WAKE.

 Activate low-power sleep mode on Host Controller by issuing 0xFC27(Vendor specific HCI command)

 Assert BT_DEV_WAKE before sending any HCI packets (commands or data) to UART.

 De-assert BT_DEV_WAKE if no more packets to be sent after a certain time.

 Before Host would like to enter sleep, suspend UART and hold flow-off by keeping Host’s UART_RTS pin de-asserted.

 When waked on BT_HOST_WAKE, resume UART and wait for UART fully functioning then assert Host’s UART_RTS pin to release flow-off.

The table in

(https://www.cypress.com/file/298081/download page 27 , gives further details of each signal.

Regards,

VinayakS_26

Check out the following link:

Re: HOST_WAKE & BT_WAKE implementation

IlBy_4632306
Level 1
Level 1

Thanks, it exactly what I need! But I want to wake up my host device from BT module.

I tried to send your hci command(Vendor specific):

$ hcitool -i hci0 cmd 0x3F 0x0027

< HCI Command: Vendor (0x3f|0x0027) plen 0                                           #1 [hci0] 3.034950

> HCI Event: Command Complete (0x0e) plen 4                                          #2 [hci0] 3.035806

      Vendor (0x3f|0x0027) ncmd 1

        Status: Invalid HCI Command Parameters (0x12)

Maybe I should use some params ?

And what event will assert BT_HOST_WAKE from BT?

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