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CP3
BT26
Table 2
CP3BT26 LQFP-128 Signal Descriptions
Name
Pins
I/O
Primary Function
Alternate
Name
Alternate Function
X1CKI
1
Input
12 MHz Oscillator Input
BBCLK
BB reference clock for the RF Interface
X1CKO
1
Output
12 MHz Oscillator Output
None
None
X2CKI
1
Input
32 kHz Oscillator Input
None
None
X2CKO
1
Output
32 kHz Oscillator Output
None
None
RESET
1
Input
Chip general reset
None
None
ENV0
1
I/O
Special mode select input with
internal pull-up during reset
PLLCLK
PLL Clock Output
ENV1
1
I/O
Special mode select input with
internal pull-up during reset
CPUCLK
CPU Clock Output
ENV2
1
I/O
Special mode select input with
internal pull-up during reset
SLOWCLK
Slow Clock Output
TMS
1
Input
JTAG Test Mode Select
(with internal weak pull-up)
None
None
TCK
1
Input
JTAG Test Clock Input
(with internal weak pull-up)
None
None
TDI
1
Input
JTAG Test Data Input
(with internal weak pull-up)
None
None
TDO
1
Output
JTAG Test Data Output
None
None
RDY
1
Output
NEXUS Ready Output
None
None
VCC
6
Input
2.5V Core Logic
Power Supply
None
None
GND
6
Input
Core Ground
None
None
IOVCC
15
Input
2.5
–
3.3V I/O Power Supply
None
None
IOGND
14
Input
I/O Ground
None
None
AVCC
1
Input
PLL Analog Power Supply
None
None
AGND
1
Input
PLL Analog Ground
None
None
ADVCC
1
Input
ADC Analog Power Supply
None
None
ADGND
1
Input
ADC Analog Ground
None
None
RFDATA
1
I/O
Bluetooth RX/TX Data Pin
None
None
SCL
1
I/O
ACCESS.bus Clock
None
None
SDA
1
I/O
ACCESS.bus Serial Data
None
None
D-
1
I/O
USB D- Upstream Port
None
None
D+
1
I/O
USB D+ Upstream Port
None
None
UVCC
1
Input
3.3V USB Transceiver Supply
None
None
UGND
1
Input
USB Transceiver Ground
None
None
ADC0
1
I/O
ADC Input Channel 0
TSX+
Touchscreen X+ contact
ADC1
1
I/O
ADC Input Channel 1
TSY+
Touchscreen Y+ contact
ADC2
1
I/O
ADC Input Channel 2
TSX-
Touchscreen X- contact