Open-Q™ 835 Development Kit based on the Snapdragon™ 835 (APQ8098) Processor User Guide Version 1.0
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Copyright Intrinsyc Technologies Corporation
3.8.5 RCM Header J0901
The RCM header is used to sense/ monitor the current on the 3.8V power rail going into the
Processor board. The table below summarizes the pin outs of header J0901.
Table 3.8-6 J10901 Pin out
Description
Signal
Pin
Processor board power positive current
sense line
SOM_PWR_SENSE_P
J0901[1]
Processor board power negative current
sense line
SOM_PWR_SENSE_N
J0901[2]
GND
GND
J0901[31-34]
3.8.6 Debug Serial UART Header J2103
Figure 9 J2103 Debug UART Header
The UART header and supporting circuitry does not come preinstalled. To have access to
the debug UART, a 3-pin header needs to be installed as well as the supporting circuitry.
Please see the carrier board schematic for details on what to install for this header to be
functional.
The header consists of TX, RX and GND pins. It is a 3.3V TTL UART header. To get the
serial terminal working with a PC, the following cable (or similar) is needed
http://www.digikey.ca/product-detail/en/TTL-232R-RPI/768-1204-ND/4382044
Table 3.8-7 J2103 Debug UART Header Pin out
Description
Signal
Pin
FTDI RPI cable
connection
APQ UART RX (GPIO5)
BLSP8_UART_RX
J2103[1]
Orange
APQ UART TX (GPIO4)
BLSP8_UART_TX
J2103[2]
Yellow
GND
GND
J2103[3]
Black
3.8.7 Debug Serial UART over USB J2102
