ADVANCE
CYW43570
Figure 31 shows the Bluetooth boot-up sequence from power-up to firmware download.
Figure 31. Bluetooth Boot-Up Sequence
VBATT/VDDIO
T1
BT_REG_ON
BT_USB_DP
BT_USB_DN
T2
T5
T3
T6
Notes:
T1: Reset control signal timing ~100 ms.
T2: BT POR and FW ROM boot time, before BT enables USB D+ pull‐up to connect the device to the host, ranges from 100 ms (ROM boot) to 250 ms
(depends on the size of FW download, based on Broadcom qualified BT Sflash).
T3: > 100 ms USB connection de‐bounce time on the host side.
T5: > 10 ms Host drives USB reset.
T6: > 10 ms Host sends USB SOF packet.
After T6: Device is ready to communicate with the host.
Document Number: 002-15054 Rev. *I
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