Data Sheet
Table Of Contents
- 1. Feature List
- 2. Typical Applications
- 3. Design Guidelines
- 4. Pin-Out Description
- 5. Power Control
- 6. Interface
- 7. Antenna
- 8. Bluetooth® Software Stack
- 9. Host Interface
- 10. Connection Examples
- 11. Electrical Characteristics
- 12. RF Characteristics
- 13. Packaging Specifications
- 14. Soldering Recommendations
- 15. Tape and Reel Packaging
- 16. Certifications
- 17. Ordering Guide
- 18. Revision History
10.2 Connecting an External Device Using I
2
C Interface
The BT122 Dual Mode Module contains one physical I
2
C peripheral. Pin configurations for the I
2
C interface are listed in Table
4.2 General Purpose I/O Pins and Their Functions on page 9. An example of this type of interfacing is shown in the figure below. Note
the pull-up resistors on the SDA and SCL lines. The example shows the address/chip select lines of the generic peripherals hardwired
to VDD, but in practice all or some of them would be wired to GPIO pins of the BT122 configured to work as chip select or address lines
controlled by the application hardware. In the example below a generic sensor chip is connected to the BT122 using the I
2
C.
1
2
3
4
5
6
7
8
20
19
18
17
16
15
14
13
9
10
11
12
GND
GND
GND
GND
GND
GND
GND GND
TOP VIEW
PA0
PA1
PC8
PC9
VDD
RESET
PF0
PF1
PF2
PF3
PF4
PF5
SCL
SDA
VDD
VSS
CTS
RTS
TX
RX
BT122
UART
BT122
GENERIC PERIPHERAL
WITH I2C INTERFACE
3V3
3V3
NC
BT122 CONNECTED TO USE
I2C
GND
RX
TX
RTS
CTS
VDD
3V3
OPTIONAL CONNECTOR ON APPLICATION PCB
ALLOWS CONTROL AND REFLASH OF MODULE
FOR EXAMPLE FROM A PC
PA0 = SCL
PA1 = SDA
INT
R
R
UP
UP
= 4.7 KOHM 50 V 0.083 W
R
UP
ADDRESS / CHIP SELECT LINES OF THE
PERIPHERAL COULDALSO BE WIRED TO
SELECTED GPIO PINS CONFIGURED ASOUTPUTS
TO ALLOW ADDRESSING SEVERAL
PERIPHERALS
Figure 10.2. Connecting to an I
2
C Peripheral
BT122 Data Sheet
Connection Examples
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