Choose the FPGA bitstream

Each PandABlocks-FPGA .ipk package ships an FPGA bitstream and declares which FMC hardware it requires. On boot, meta-panda selects the bitstream to load as follows:

1. If the APP variable is set in config.txt, that bitstream is used.

2. Otherwise the PandA reads the FMC EEPROM and auto-selects the bitstream whose FMC requirements match.

3. If more than one installed bitstream would satisfy the EEPROM check, the PandA reports an error.

Automatic selection¶

Leave APP unset in config.txt. The PandA will select the bitstream that matches the FMC card detected at boot. If no FMC EEPROM is found, the no-fmc variant is used.

Manual override via APP¶

To force a specific bitstream, add APP=<variant> to config.txt on the SD card:

APP = pandabox-fmc-acq430

The APP variable takes effect only if the corresponding FPGA variant package is installed. Available variant names are listed in the package names visible in the web admin (Packages → List Installed Packages).

USB override (no SD card access needed)¶

To override without opening the PandA, add APP=<variant> to panda-config.txt on a USB stick and plug it in while the PandA boots:

APP = pandabox-fmc-acq430

See How to get a PandA on the network without DHCP for full details of the USB override mechanism.

Installing a new bitstream package¶

scp panda-fpga-<variant>_<version>.ipk root@<panda-hostname>:/tmp/
ssh root@<panda-hostname> opkg install /tmp/panda-fpga-<variant>_<version>.ipk
ssh root@<panda-hostname> reboot

To build a custom bitstream package from source, see the PandABlocks-FPGA documentation.