ADVANCE
CYW43570
Figure 5. Startup Signaling Sequence
LPO
VDDIO
Host I/Os unconfigured
Host IOs configured
HostResetX
T1
BT_DEV_WAKE
BT_REG_ON
T4
BT I/Os unconfigured
BT I/Os configured
BT_HOST_WAKE
Tsettle
T2
Indicates that the
BT device is ready
T3
BT_UART_RTS_L
BT_UART_CTS_L
BT_CLK_REQ
Tsettle
Driven
Pulled
Notes :
T1 is the time for host to settle its IOs after a reset.
T2 is the time for the BTH device to settle its IOs after a reset and reference clockk settling time elapsed.
T3 is the time for the BT device to complete initialization and drive BT_UART_RTS_L low.
T4 is the setup time for BT_DEV_WAKE prior to driving BT_REG_ON high; BT_DEV_WAKE must be high prior to BT_REG_ON being
released. BT_DEV_WAKE should not be driven low until after the host has completed configuration.
Tsettle is the time for the reference clock signal from the host to be guaranteed to have settled.
Document Number: 002-15054 Rev. *I
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