Build and run a sequence of CAN frame commands
Tip: top-level Group blocks act as notebook cells — each one gets its own ▶ Run button, and `set` variables persist across cell runs.
Tip: click a block to select it, then shift+click another block (same parent) to select the range. Drag any one of them to move all together. Esc clears the selection.
Closed-loop: use Bind to feed a received signal into a variable continuously, or Read to wait once for the next frame. The variable is then usable in any later `=expr` field.