BC41B143A-DS-002PD Datasheet, PDF (78/89 Pages) List of Unclassifed Manufacturers – BlueCore 4-ROM CSP EDR Single Chip Bluetooth v2.0 + EDR System

Device Terminal Descriptions
11.9 I²C Master
PIO[8:6] can be used to form an interface. The interface is driven by “bit banging” these PIO pins using software.
Therefore it is suited only to relatively slow functions such as driving a dot matrix liquid crystal display (LCD),
keyboard scanner or EEPROM.
Note:
PIO[7:6] dual functions, UART bypass and EEPROM support, therefore devices using an EEPROM cannot
support UART bypass mode.
PIO lines need to be pulled-up through 2.2kΩ resistors.
For connection to EEPROMs, refer to CSR documentation on I²C EEPROMS for use with BlueCore. This
provides information on the type of devices that are currently supported.
+1.8V
PIO[8]
PIO[6]
PIO[7]
10nF
2.2kΩ 2.2kΩ 2.2kΩ
U2
8 _{VCC A0} 1
7 _WP
A1 ²
6 _{SCL A2} 3
5 _{SDA GND} 4
Serial EEPROM
(AT24C16A)
Figure 11.28: Example EEPROM Connection
11.10 TCXO Enable OR Function
An OR function exists for clock enable signals from a host controller and BlueCore4-ROM CSP where either
device can turn on the clock without having to wake up the other device. PIO[3] can be used as the Host clock
enable input and PIO[2] can be used as the OR output with the TCXO enable signal from BlueCore4-ROM CSP.
VDD
TCXO
Enable
GSM System
CLK IN
CLK REQ OUT
BlueCore System
CLK REQ IN/
PIO[3]
CLK REQ OUT/
CLK IN
PIO[2]
Figure 11.29: Example TXCO Enable OR Function
On reset and up to the time the PIO has been configured, PIO[2] is tri-stated. Therefore, the developer must
ensure that the circuitry connected to this pin is pulled via a 470kΩ resistor to the appropriate power rail. This
ensures that the TCXO is oscillating at start up.
BC41B143A-ds-002Pd
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