Renode Development Workflow (TMNL)

When to Use

• Editing .resc scripts or swapping firmware.
• Debugging UART output or monitor commands.
• Troubleshooting silent telemetry.

Canonical Sources

• embedded/renode/nrf52840/nrf52840-telemetry.resc
• embedded/renode/scripts/renode-init.sh
• embedded/renode/README.md

Standard Loop

1. Update .resc (firmware path, UART port, or board).
2. Restart Renode via renode-init.sh.
3. Verify monitor access (nc 127.0.0.1 1234).
4. Verify UART traffic (nc 127.0.0.1 5501).

Pattern 1: Swap Firmware

When: You need a different ELF or build.

sysbus LoadELF @path/to/firmware.elf

Restart the tmux session after editing:

tmux kill-session -t tmnl-renode
embedded/renode/scripts/renode-init.sh

Pattern 2: Adjust UART Port

When: Port collision or multi-session debugging.

CreateServerSocketTerminal 5501 "uart_socket" false
connector Connect sysbus.uart0 uart_socket

Set the matching environment override before launch:

export TMNL_RENODE_UART_PORT=5501
embedded/renode/scripts/renode-init.sh

Pattern 3: Monitor Commands

When: You need control over machine state.

help
machine Start
machine Reset
sysbus.uart0

Pattern 4: Inject Monitor Commands (tmux)

When: You need to drive the monitor without switching panes.

embedded/renode/scripts/renode-send-keys.sh "machine Reset"
embedded/renode/scripts/renode-send-keys.sh "machine Start"

Decision Tree: UART Silence

UART silent?
├─ Monitor reachable? -> nc 127.0.0.1 1234
├─ Connector present? -> ensure "connector Connect sysbus.uart0 uart_socket"
└─ Firmware loaded?   -> verify LoadELF path in .resc

DO NOTs (Strict)

• DO NOT use PTY UART terminals. Use TCP sockets + nc.
• DO NOT run Renode with GUI in tmux workflows.
• DO NOT start multiple Renode sessions on the same ports.
• DO NOT bypass .resc scripts with manual monitor setup.

Guardrails (Mandatory)

• Keep CreateServerSocketTerminal in every .resc script.
• Use --disable-gui (handled by renode-init.sh).
• Keep UART and monitor ports documented in README.
• Use one tmux session per Renode instance.

Highly Suggested

• Keep firmware paths relative to embedded/renode/.
• Validate the monitor socket before debugging UART.
• Keep a known-good .resc for quick rollback.

Files to Edit

• embedded/renode/nrf52840/nrf52840-telemetry.resc
• embedded/renode/scripts/renode-init.sh
• embedded/renode/scripts/renode-send-keys.sh
• embedded/renode/README.md