Accelerometer wiring
Looks right to me,
ADXL345 &gt; Net &lt; Feather
GND     &gt; GND &lt; GND
SCL 14  &gt; SCK &lt; 24, Pin 20
SDA 13  &gt; MOSI &lt; 23, Pin 19
SDO 12  &gt; MISO &lt; 22, Pin 21
CS 7    &gt; CS  &lt; SW Defined
Vdd I/O 1 &gt; V+ &lt; 3V
Probably want a decoupling cap on the supply to the ADXL345 as well.