stlc2410 STMicroelectronics, stlc2410 Datasheet - Page 17

• Manufacturer Part Number: stlc2410
• Description: Bluetooth Baseband
• Manufacturer: STMicroelectronics

Figure 7. PCM interface timing
8
The UART Transport Layer is specified by the Bluetooth
nication between a host controller (STLC2410B) and a host (e.g. PC), via a RS232 interface.
The objective of this HCI UART Transport Layer is to make it possible to use the Bluetooth
serial interface between two UARTs on the same PCB. The HCI UART Transport Layer assumes that the
UART communication is free from line errors.
8.1 UART Settings
The HCI UART Transport Layer uses the following settings:
– Baud rate: Configurable (Default baud rate: 57.6 kbits/s)
– Number of data bits: 8
– Parity bit: no parity
– Stop bit: 1 stop bit
– Flow control: RTS/CTS
– Flow-off response time: 3 ms
Flow control with RTS/CTS is used to prevent temporary UART buffer overrun. It should not be used for
flow control of HCI, since HCI has its own flow control mechanisms for HCI commands, HCI events and
HCI data.
If CTS is 1, then the Host/Host Controller is allowed to send.
If CTS is 0, then the Host/Host Controller is not allowed to send.
The flow-off response time defines the maximum time from setting RTS to 0 until the byte flow actually
stops. The signals should be connected in a null-modem fashion; i.e. the local TXD should be connected
to the remote RXD and the local RTS should be connected to the remote CTS and vice versa.
Figure 8. UART Transport Layer
HCI UART TRANSPORT LAYER
BLUETHOOTH
PCM_B/A out
PCM_SYNC
PCM_A/B in
PCM_CLK
HOST
t
WCH
HCI UART TRANSPORT LAYER
t
WSH
t
BLUETHOOTH HCI
WCL
t
SSC
MSB
MSB
MSB-1
t
SDC
MSB-1
t
DCD
®
SIG ( Part H:4), and allows HCI level commu-
MSB-2
MSB-2
BLUETHOOTH
CONTROLLER
MSB-3
t
HCD
MSB-3
HOST
MSB-4
D02TL557
MSB-4
D02TL556
STLC2410B
®
HCI over a
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