Data Sheet

SGW111X BLE Modules Series Datasheet
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The SGW111X series modules also supports parallel trace output. This allows output from the
Embedded Trace Macrocell (ETM) and Instrumentation Trace Macrocell (ITM) embedded in the
Arm Cortex-M4 core of the nRF52840 chip. The ETM trace data allows a user to record exactly
how the application goes through the CPU instructions in real time. The parallel trace interface
uses 1 clock signal and 4 data signals respectively - TRACE_CLK, TRACE_D0, TRACE_D1,
TRACE_D2 and TRACE_D3.
7.3.5. Clocks
The SGW111X series modules requires two clocks: High frequency and low frequency clock.
The high frequency clock is provided by the on-board 32MHz crystal.
For the low frequency clock, it supports several low-frequency 32.768kHz clock sources:
o 32.768 kHz +/-500 ppm nRF52840 internal RC oscillator
o 32.768 kHz oscillator synthesized from on-board oscillator
o 32.768 kHz crystal oscillator, using external 32.768 kHz crystal
Figure 6. Low Frequency Clock Reference Circuit – External Crystal