Interfaces and Connectors
Bengal (VL-EPMe-30) Reference Manual
41
PCIe Mini Card LEDs
Two dual-colored PCIe Mini Card LEDs are provided on the Bengal at locations D8 and D9. Table
22 lists the states of the LEDs.
Table 22: PCIe Mini Card LED States
LED
Color
Status (when lit)
D8
Green
Activity on Wireless WAN (Note)
Yellow
Activity on Wireless LAN (Note)
D9
Green
Activity on Wireless PAN (Note)
Yellow
Illuminates when the 3.3 V power to the Mini
Card is on. It alerts users to not hot-plug the
Mini Card. By default, Mini Card power stays
on when the processor is in sleep modes.
Note:
These LEDs will illuminate when the associated device is installed
and capable of transmitting. Their function is determined by the installed
device.
Integrator’s Note:
The 3.3 V power to the Mini Card can be controlled by the FPGA. By default, the power is always
on, but there is a register setting that turns this power off in sleep modes. The 1.5 V power is
always turned off in sleep modes.
Digital I/O
The 20-pin I/O connector (J21) incorporates 16 digital I/O (DIO) lines that are independently
configurable as an input or output. DIO inputs can be set for normal or inverted level. DIO outputs
can be set to be normal HIGH or LOW state. There are pull-up resistors to +3.3 V on all DIO lines.
The pull-ups implemented
— in the FPGA — can range in value from 20 kΩ to 40 kΩ. After reset,
the DIO lines are set as inputs with pull-ups that will be detected as a HIGH state to external
equipment.
VersaLogic provides a set of application programming interface (API) calls for managing the DIO
lines. See the
Table 23 shows the function of each J21 pin and how they are routed to the paddleboard.
