I2C (Snap I2C); Spi (Snap Spi); Adc; Gpio Expansion Header - NXP Semiconductors TWR-RF-SNAP User Manual

I2C (SNAP I2C):

- Connected to Physical Pins 28-29 – SNAP GPIO 13-12
- SCL = Pin_29/GPIO_12, SDA = Pin_28/GPIO_13
- This interface port attaches to edge-connectors (elevator) for communication with other
devices within the Tower System as well as the on-board TWRPI socket

SPI (SNAP SPI):

- Connected to Physical Pins 35, 39-41 – SNAP GPIO 7-4
- SCK = Pin_35/GPIO_7, MOSI = Pin_39/GPIO_6, MISO = Pin_40/GPIO_5, SS = Pin_41/GPIO_4
- This serial interface bus attaches to edge-connectors (elevator) for communication with other
devices within the Tower System

ADC:

- ADC1 has the capability to use an on-board 2.5V precision voltage reference

GPIO Expansion Header:

- The GPIO header exposes the following pins for use external to the TWR-RF-SNAP board:
GPIO Header (J6)
1
2
3
4
5
6
7
8
9
10 SNAP GPIO_20 / UART1_CTS (SNAP SW UART0)
TWR-RF-SNAP User's Manual
Pin Description
SNAP GPIO_28 / Keyboard Interrupt 6 (KBI_6)
Vcc (3.3V)
SNAP GPIO_29 / Keyboard Interrupt 7 (KBI_7)
SNAP GPIO_0 / SSI_TX
SNAP GPIO_1 / SSI_RX
SNAP GPIO_2 / SSI_FSYN
SNAP GPIO_3 / SSI_BITCK
SNAP GPIO_21 / UART1_RTS (SNAP SW UART0)
GND
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