WT11i-A-AI3 Bluegiga Technologies, WT11i-A-AI3 Datasheet - Page 21

• Manufacturer Part Number: WT11i-A-AI3
• Description: Bluetooth / 802.15.1 Modules WT11i Class1 2.1+EDR Chip Ant, iWRAP 3.0
• Manufacturer: Bluegiga Technologies

Specifications of WT11i-A-AI3

• Rohs: yes
• Class: 1
• Frequency Band: 2.4 GHz
• Sensitivity: - 83 dBm
• Operating Supply Voltage: 3.3 V
• Output Power: 17 dBm
• Interface Type: GPIO, UART, USB
• Antenna Connector Type: Chip
• Maximum Operating Temperature: + 85 C
• Dimensions: 35.8 mm x 14.5 mm x 2.3 mm
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT

5.1 UART Bypass
Figure 17: UART Bypass Architecture
5.2 UART Configuration While Reset is Active
The UART interface for WT11i while the chip is being held in reset is tristate. This will allow the user to daisy
chain devices onto the physical UART bus. The constraint on this method is that any devices connected to
this bus must tristate when WT11i reset is de-asserted and the firmware begins to run.
5.3 UART Bypass Mode
Alternatively, for devices that do not tristate the UART bus, the UART bypass mode on BlueCore4-External
can be used. The default state of BlueCore4-External after reset is de-asserted; this is for the host UART bus
to be connected to the BlueCore4-External UART, thereby allowing communication to BlueCore4-External via
the UART. All UART bypass mode connections are implemented using CMOS technology and have signalling
levels of 0V and VDD.
In order to apply the UART bypass mode, a BCCMD command will be issued to BlueCore4-External. Upon
this issue, it will switch the bypass to PIO[7:4] as Figure 17 indicates. Once the bypass mode has been
invoked, WT11i will enter the Deep Sleep state indefinitely.
In order to re-establish communication with WT11i, the chip must be reset so that the default configuration
takes effect.
It is important for the host to ensure a clean Bluetooth disconnection of any active links before the bypass
mode is invoked. Therefore, it is not possible to have active Bluetooth links while operating the bypass mode.
The current consumption for a device in UART bypass mode is equal to the values quoted for a device in
standby mode.
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