Basic network operations - InnoRoute/RealtimeHAT GitHub Wiki

This tutorial require minimum release r0.2 of the codebase.

Initial access to the RPI

Once a new Image was downloaded or the Update-script was launched, the RPI is available via DHCP on its eth0 interface. After running an update, the RealTime-HAT network connection is not available. In this mode its wise to ensure to have the wifi connection available as management interface for further steps.

Activating the HAT's network function.

The network function of the HAT depends on the loaded FPGA configuration. The actual FPGA configuration is loaded during startup automatically by the script /etc/init.d/INR_FPGA_load. To activate the automatic FPGA configuration the file /usr/share/InnoRoute/user_bitstream.bit is required. To download/update your personal FPGA configuration the script /usr/share/InnoRoute/INR_update_bitstream.sh needs to be launched. This will download your user_bitstream.bit and activate the automatic load during startup.

Used kernel modules

By successfully loading your user_bitstream.bit the Realtime-HAT network driver is activated by loading the INR_RTHAT kernel module. This Module is an DSA network extension providing two interfaces RT0 and RT2 on top of eth0. If the DSA module is loaded the eth0 network interface will not work for other connections, please ensure you are connected via wifi.

Network access using the RealTime-HAT

To use the RealTime-HAT network functions the middle interface of the HAT #1 needs to be connected to the Raspberries network interface. If a FPGA design with activated network is loaded and the INR_RTHAT kernel module is loaded, the interfaces RT0 and RT2 can be handled as normal network interfaces, they correspond with the physical interfaces #0 and #2 on your RealTime-HAT. You can request a DHCP addresses, bridge them, use PTP etc.

• Note: in the actual Release-r0.2 the RealTime-HAT just supports 1GbE interface speed, 100M connections could not be established.