NRF51822-CFAB-R datasheet(31/130 Pages) NORDIC

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Page 31

nRF51822 Product Specification v3.3

3.6.4

Synthesized 32.768 kHz clock

The low frequency clock can be synthesized from the high frequency clock. This saves the cost of a crystal

but increases average power consumption as the high frequency clock source will have to be active.

3.7

GPIO

The general purpose I/O is organized as one port with up to 32 I/Os (dependent on package) enabling

access and control of up to 32 pins through one port. Each GPIO can be accessed individually with the

following user configurable features:

•Input/output direction

• Output drive strength

• Internal pull-up and pull-down resistors

• Wake-up from high or low level triggers on all pins

• Trigger interrupt on all pins

• All pins can be used by the PPI task/event system. The maximum number of pins that can be

interfaced through the PPI at the same time is limited by the number of GPIOTE channels.

• All pins can be individually configured to carry serial interface or quadrature demodulator

signals.

3.8

Debugger support

The two pin Serial Wire Debug (SWD) interface provided as a part of the Debug Access Port (DAP) offers a

flexible and powerful mechanism for non-intrusive debugging of program code. Breakpoints and single

stepping are part of this support.

NRF51822-CFAB-R 数据表(PDF) 31 Page - Nordic Semiconductor