User's Manual

System Overview and Functional Block Descriptions
1322x-LPB Reference Manual, Rev. 1.1
Freescale Semiconductor 3-13
3.8.5 UART Connector
The UART connector (J3) is a standard 2.54mm/0.1inch spacing, 6-pin header. The connector provides
access to the unbuffered UART1 signals. Power is also provided on the connector.
• VCC is the main board supply voltage. Current draw should be limited to 50 mA.
• If low power mode is enabled on the module, all signals on J3 must be not be driven high.
• Signals are unbuffered for RS232; an adaptor board is needed to talk to a PC serial COM port
4I2C_SCL I
2
C Bus clock / GPIO12 I
2
C bus signal SCL. Pull-up to SW_VCC
available
5 TMR3 Timer 3 IO signal / GPIO11 Pin can be used as Counter 3 output or counter
input clock.
6 TMR1 Timer 1 IO signal / GPIO9 Pin can be used as Counter 1 output or counter
input clock.
7 ADC3 ADC analog input Channel 3/ GPIO33 ADC sample channel can be used by either
ADC1 or ADC2.
8 ADC2 ADC analog input Channel 2/ GPIO32 ADC sample channel can be used by either
ADC1 or ADC2.
9 SWITCH1 KBI_4 input/ GPIO26 Asynchronous interrupt input can be used as
wake-up signal.
10 SWITCH2 KBI_0_HST_WK output/ GPIO22 Can be used as a wake-up indicator output to
external device.
11 GND System ground
12 SW_VCC Switched voltage supply
Table 3-3. UART Connector J3 Pinouts
Pin
Number
Name Function Notes
1 UART1_RX UART1 RX data input / GPIO19 UART2 receive data input.
2 UART1_TX UART2 TX data output / GPIO18 UART2 transmit data output.
3 UART1_CTS
UART1 Clear to Send output / GPIO16 UART1 CTS control output.
4 UART1_RTS UART1 Request to Send input / GPIO17 UART1 RTS control input.
5 GND System ground
6 VCC Main voltage supply
Table 3-2. GPIO Connector J2 Pinouts (continued)