APF27 PPS

Description

PPS is an Armadeus System's baseboard for the APF27 module. It can be used to implement and securize network applications such as routers and gateways.

Front side, you can see dual Ethernet, USB 2.0 Host & OTG, WiFi Antenna, extension connector footprint and power supply

Back side, with an APF27 module plugged-in

Resources

• Product page on Armadeus Systems website
• Schematics
• Datasheet
• Mechanical drawings

Software features

There are some network applications/features that are preselected in the PPS baseboard default configuration:

• Encryption / Security
  • OpenSSH
  • IPSec / IPTables
• USB Ethernet gadget support
• USB RS232 gadget support
• SMSC USB to Ethernet Adapter
• Boa Web Server
• Wireless tools (for securized WiFi with WEP encryption)
• WPA supplicant (for securized WiFi with WPA/WPA2 encryption)

Note: You can also use the PPS test scripts located in /usr/local/pps/scripts on the system to test some software functionalities.

SSH terminal

The APF27 PPS filesystem is configured to enable SSH connection from a host computer. It allows you to access a system terminal through the default Ethernet port (the one aside USB Host connector).

• The default connection informations are:
  • IP address: 192.168.0.10
  • Login: guest
  • Password: armadeus

• Then you can connect to your system by running the following command on your host:

 $ ssh guest@192.168.0.10

• For more details, refer to the SSH - Dropbear page in the Wiki.

Debug / Development interface

In order to gain access to the serial port of the APF27 (U-Boot & Linux console), a small adapter cable has to be done. A standard 2.54mm pin header connector (J5) allows accessing the TX and RX debug lines of the iMX27. The signals are compatible with a the RS232 standard so no level translator is required.

The pinout is described in the datasheet and summarized here:

• pin 1 (square pad): not connected
• pin 2: TX line (processor side)
• pin 3: RX line (processor side)
• pin 4: GND

J5 pin 1

DB9 connection like on APF27Dev (requires Null-Modem cable)

DB9 connection for direct USB<->Serial adapter usage

WiFi usage

On PPS, WiFi/Libertas driver usage is a little bit different than on other platforms. Here are the things to know:

Drivers setup

You have to install Libertas SDIO and MMC drivers as modules to make Wi2Wi chipset work correctly on PPS (done by default):

$ make linux26-menuconfig

Device drivers  --->
    [*] Network device support  --->
        Wireless LAN  --->
            [*] Wireless LAN (IEEE 802.11)
            <M>   Marvell 8xxx Libertas WLAN driver support
            < >     Marvell Livertas 8388 USB 802.11b/g cards
            <M>     Marvell Libertas 8385 and 8686 SDIO 802.11b/g cards
    <M> MMC/SD/SDIO card support  --->
              *** MMC/SD/SDIO Card Drivers ***
        <M>   MMC block device driver

Initializing the connection

Before creating the WiFi connection, you must load the Libertas SDIO and the MMC modules:

# modprobe mxcmmc
# modprobe libertas_sdio

Then all informations on Libertas_driver page apply.

Disconnect from the WiFi

You have to unload the MMC driver along with the Libertas SDIO to disconnect from the WiFi:

modprobe -r mxcmmc
modprobe -r libertas_sdio

Reset Wi2Wi

To reset the chipset, you have to use the Wi2Wi RESET GPIO:

source /usr/bin/gpio_helpers.sh

gpio_mode PE11 1
gpio_set_value PE11 0
gpio_set_value PE11 1

Feature list

Wired communication UART SPI I2C USB Host USB OTG Ethernet Wireless communication Wi2Wi chipset driver (see Wi2Wi Section) WiFi usage on Linux

Other PWM: PWM output is on J22 pin 4 (2.8V output, if configured as output) GPIO Driver JTAG

FPGA Using FPGA