96Boards ROCK960 User Manual page 15

The ROCK960 board implements this requirement. All GPIOs are routed to the
RK3399 SoC. Refer the Low Speed Expansion Connector table for GPIO A-L
signals. The GPIO of RK3399 has following features:
All of GPIOs can be used to generate interrupt to CPU
GPIO0 and GPIO1 can be used to wakeup system from low-power mode
The pull direction(pull-up or pull-down) for all of GPIOs are software-programmable
All of GPIOs are always in input direction in default after power-on-reset
The drive strength for all of GPIOs is software-programmable
SPI 0
The 96Boards specification calls for one SPI bus master to be provided on the Low Speed
Expansion Connector.
The ROCK960 Board implements a full SPI master with 4 wires, CLK, CS, MOSI and MISO. The
signals are connected directly to the RK3399 SoC and driven at 1.8V.
PCM/I2S
The 96Boards specification calls for one PCM/I2S bus to be provided on the Low Speed Expansion
Connector. The CLK, FS and DO signals are required while the DI is optional.
The ROCK960 Board implements a PCM/I2S interface with 4 wires, CLK, FS, DO and DI. The
signals are connected directly to the RK3399 SoC and driven at 1.8V.
Power and Reset
The 96Boards specification calls for a signal on the Low Speed Expansion Connector that can
power on/off the board and a signal that serves as a board reset signal.
The ROCK960 Board routes the PWR_BTN_N (named PMIC_PWRON on schematic) signal to the
PWRON pin of the PMIC RK805. A mezzanine implementation of this signals should not drive it
with any voltage, the only allowed operation is to force it to GND to start the board from a sleep
mode.
The ROCK960 Board routes the RST_BTN_N (named RESET_L on schematic) signal to the
NRESPWRON pin of the PMIC RK805. This signal is also routes to SW2100, a push button for
reset.
Power Supplies
The 96Boards specification calls for three power rails to be present on the Low
Speed Expansion Connector:
+1.8V Max of 100mA
+5V Provide a minimum of 5W of power (1A).
SYS_DCIN 8-18V input with enough current to support all the board functions or the
output DCIN from on-board DC Connector able to provide a minimum of 7W of
power.
The ROCK960 Board supports these requirements as follows: