Hardware description
4.10 External memory
The nRF9160 DK has a 64 Mb external flash memory. The memory is a multi-I/O memory supporting both
SPIs.
The memory is connected to the chip using the following
s:
GPIO
Flash memory pin
Solder bridge for default
use
Testpoint
P0.25
CS
SB23
TP57
P0.13
SCLK
N/A
N/A
P0.11
SIO_0/SI
N/A
N/A
P0.12
SIO_1/SO
N/A
N/A
N/A
SIO_2/WP
N/A
TP55
N/A
SIO_3/HOLD
N/A
TP56
Table 8: Flash memory GPIO usage, solder bridges and testpoints
The flash memory CS pin is by default connected to
P0.25
, this pin is also used for trace. To be able to
use the external memory together with trace, Solder bridge
SB23
can be cut and a wire can be strapped
from test point
TP57
to a GPIO of choice. The WP and HOLD pins of the external memory are available
only on test points
TP55
and
TP56
, and to use these, wires can be strapped form the test points to the
GPIOs of choice.
GND
4
VCC
8
CS
1
SIO0/SI
5
SIO2/WP
3
SCLK
6
SIO3/RESET
7
SIO1/SO
2
U37
MX25R6435FZNIL0
C84
100nF
VDD
SCK
CS
MOSI
MISO
WP
RESET
MEMORY
EXT_MEM
R110
100k
EXT_MEM_CS
EXT_MEM_WP
EXT_MEM_RESET
EXT_MEM_MISO
EXT_MEM_MOSI
EXT_MEM_SCK
R111
100k
VDD
Figure 21: Flash memory
4.11 Debug input and trace options
The primary debug interface on the nRF9160 DK is the Segger OB debugger available through the
port. However, if other than USB supply is used on the
, this functionality will be disabled.
The Debug in connectors
P18
(nRF9160) and
P23
(nRF52840) make it possible to connect external
debuggers for debugging when the interface USB cable is not connected or if the DK is in IF MCU
DISCONNECT mode.
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