Connect to your Device Under Test

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Once you've logged in and confirmed that your gateway is receiving commands, you'll need to connect to your DUT. We'll do this using the lager connect command. This command lets the Lager Gateway know what kind of device it is connected to, and how it is connected. For brevity we'll omit the --gateway <name> flag, but you'll need to include it if you have more than one gateway.

Connect flags


Identifies the Device Under Test which is connected to your gateway. See below for a list of supported devices. Example usage: lager connect --device nrf52.

lager_cli.SUPPORTED_DEVICES = ('at91samdexx', 'at91samdgxx', 'at91samdxx', 'atsame70', 'cc3220s', 'cc3220sf', 'cc3235sf', 'efm32', 'nrf52', 'stm32f0x', 'stm32f1x', 'stm32f2x', 'stm32f3x', 'stm32f4x', 'stm32f7x', 'stm32g0x', 'stm32g4x', 'stm32h7x', 'stm32h7x_dual_bank', 'stm32l0', 'stm32l0_dual_bank', 'stm32l1', 'stm32l1x_dual_bank', 'stm32l4x', 'stm32mp15x', 'stm32w108xx', 'stm32wbx', 'stm32wlx', 'stm32xl', 'imxrx1050', 'imxrx1064')


Debug transport protocol. Available options are swd, jtag, or hla_swd. Defaults to swd. Example: lager connect --device nrf52 --transport swd


Debug interface driver. Available options are ftdi, jlink, cmsis-dap, xds110, stlink, or stlink-dap. Defaults to ftdi. Example: lager connect --device nrf52 --interface ftdi


Adapter speed in kHz. This may be omitted, in which case the Lager Gateway will attempt to determine the speed automatically.

Putting it all together

lager connect --device nrf52 --transport swd --interface ftdi --speed 4000

➜  ~ lager connect --device nrf52 --transport swd --interface ftdi --speed 4000

Verify connection

Finally, we'll want to verify that our debugger is up and running. For that we'll use lager gateway status.

➜  ~ lager gateway status
Debugger running: True
---- Debugger config ----
interface: ftdi_2232
transport select swd
target: nrf52
---- Logs ----
Info : FTDI SWD mode enabled
Info : Listening on port 6666 for tcl connections
Info : Listening on port 4444 for telnet connections
Info : clock speed 1000 kHz
Info : SWD DPIDR 0x2ba01477
Info : nrf52.cpu: hardware has 6 breakpoints, 4 watchpoints
Info : starting gdb server for nrf52.cpu on 3333
Info : Listening on port 3333 for gdb connections