Interacting with Passthrough Maps

Every passthrough channel in the system. Call new() to build the map and routing context, optionally route() required hops, then resolve() to fill channel-map chains.

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Columns

Columns are automatically generated when passthrough_map.new() is called. Additional columns are ok but discouraged due to consistency. If you need more columns, use data structures in build instructions.

Column	Description
from_channel_type	channel-map from type
from-passthrough_channel_type	passthrough face on the same side as from
to-passthrough_channel_type	passthrough face on the same side as to
to_channel_type	channel-map to type
requirement	user route() step number for this passthrough-channel mapping
satisfaction	resolve() route() step number (always >= requirement when both set)
is_imaginary	TRUE if this mapping was minted because no real passthrough channel was available
has_imaginary	TRUE if this passthrough device has any imaginary channel mappings
manual_map_passthrough_python_equiv	passthrough_map.route() that would form this requirement

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Commands

These functions are already available in build instructions as passthrough_map. Use them as written.

passthrough_map.read()

Use this when a system build needs every row of the passthrough map in the revision that is open.

Return the passthrough map (cached).

passthrough_map.new()

Use this when a system build needs passthrough rows created from the signals lists of the devices on the block diagram.

Create passthrough channel rows from placed-device signals lists.

Rebuilds system.passthrough_routing_context as one row per unique (from_channel_type, to_channel_type) pair within each group_of_connected_harnesses, per passthrough device, per directionality (1 / -1, or 0 if reversible), with an availables count of passthrough channels that obey that directionality. Does not route channels or fill channel-map chains (see resolve()).

passthrough_map.route(to_from_channel_device_refdes, to_from_channel_id, intended_device_refdes, intended_channel_id=None, repeat_channel_id=None, satisfaction=False)

Use this when a system build needs one mapped channel sent through one passthrough device.

Route a mapped channel through a passthrough device.

Looks up the mapped channel's from→to types and group_of_connected_harnesses, finds the matching routing-context row(s), picks a free passthrough channel that obeys directionality, records the mapping on the passthrough map, and decrements availables on the matching context row (never below 0).

repeat_channel_id is the face the from-side arrives on. Omit it to infer.

The passthrough device must belong to the same group_of_connected_harnesses as the mapped channel.

By default writes requirement (user route). With satisfaction=True (used by resolve), writes satisfaction instead.

Returns 0 on a real assignment, -1 if an imaginary passthrough-map row was appended because availables was already 0.

Args: - to_from_channel_device_refdes: Device refdes of the mapped channel you are routing. - to_from_channel_id: Channel id on that device. - intended_device_refdes: Passthrough device to route through. It must belong to the same group of connected harnesses as the mapped channel. - intended_channel_id: Specific passthrough channel to use. Optional. Omit it to let route pick a free channel that matches directionality. - repeat_channel_id: Face the from-side arrives on. Optional. Omit it to infer the face. - satisfaction: When True, write a satisfaction row (what resolve does). When False, write a requirement row. Optional.

passthrough_map.resolve()

Use this when a system build needs every mapped channel routed through its passthroughs, in channel-map order.

Complete passthrough routing for each mapped channel (channel-map order).

Uses the routing context (filtered to group_of_connected_harnesses + from→to pair) to find the fewest passthrough channels that connect from_harness → optional ordered requirement waypoints → to_harness. Prefers paths with remaining availables; if none exist, allows availables == 0 (imaginaries).

Gap fills call route(..., satisfaction=True). Existing requirement rows get a satisfaction stamp. Writes chain_of_connectors and chain_of_harnesses on each mapped channel-map row from the resulting path.

Stamps is_imaginary / has_imaginary on the passthrough map. Prints one warning per passthrough that needed imaginary channels to satisfy the map.

No-op when passthrough_map.new() found no harness topology (empty parent diagram / no harness-mated connectors): there is nothing to resolve.