4 Conformance

4.1 Core and product types

A product conforms to EIS when it meets every shall that applies to it. Two things decide which apply:

Its product type and roles. Each requirement names the product types it applies to. A product owes those of its product type and of every other role it plays, such as a supply built into a case (roles).
What it has. A requirement about a power entry, an outlet, a port of a class, or a video sync port applies only to a product that has one. The product lists these in its claim file.

Core, Part 2, is what every product meets; it is never claimed. The optional interfaces of Part 3, the 12 V DC rail and the video sync, apply only to a product that has them. A module's patch jacks each name a signal class, AUDIO, CV, VIDEO, and the rest (7.2), or unclassified, and a module mixes them freely. A bus board's or an enclosure's port list is the video_75 block of its claim file.

eis claim applies exactly this rule: it lists the shalls that bind one of the product's roles and whose condition, if the register names one, the product meets.

Product types

Product type	What its requirements cover	Clauses
module	Front panel, board clearance, patch jacks and their safety, power entries and header current, and the port list with signal classes and the formats of its rear video sync ports. A DC entry panel or a video sync distributor in module form keeps the rules of what it carries	5.1, 5.2, 6.1, 6.3, 6.4, 6.6, 7.1, 7.2, 7.3, 8.1, 8.2, 8.3
enclosure	Rack frame, rails, inserts, mounting screws, and the published width and depth of each row. A built-in supply plays the power supply role and a built-in bus board the bus board role; a case DC entry keeps the PWR-DC12 entry rules	5.1, 5.2, 5.3, 5.4, 6.1, 6.3, 6.5, 7.1, 8.1, 8.2, 8.3
bus board	Headers, links, published capacity, one 0 V, and row wiring terminals, and the rules of anything else it carries behind the panel: a DC rail or the video sync tree	6.1, 6.3, 6.4, 6.5, 7.1, 8.1, 8.2, 8.3
power supply	Rails, output connector, protection, published ratings and ripple, the earth bond of 0 V, and row wiring terminals, for a row or for the one product it is mounted on. A supply may also make the 12 V DC rail	6.1, 6.2, 6.3, 6.4, 6.5, 7.1, 8.1
cable	The interface it mates: power ribbon, video, or DC	6.4, 6.5, 8.1, 8.2

What a product has

A product does not claim its power entries or video sync ports; it lists them in its claim file. A requirement about one applies to a product that has one: the PWR-BUS entry rules to a product with a power header, the PWR-DC12 outlet rules to a product with DC outlets, the COAX-THRU rules to a product with a video sync through. A passive module has no power entry and owes no rule of the bus but BUS-011, which binds every module (6.4). The register names the condition in brackets after a row's product types:

In brackets	The row applies when	Rows
PWR-BUS	The product has a power header, or bus outlets, or is a power ribbon	7
PWR-BUS entry	The product takes the bus at a power header (power.entries, interface PWR-BUS)	8
PWR-BUS outlet	The product gives the bus at outlets: a supply's terminals, a bus board's headers (power.outlets, interface PWR-BUS)	4
PWR-DC12	The product has a DC entry or PWR-DC12 outlets, or is a DC cable	4
PWR-DC12 entry	The product takes 12 V DC at a DC entry (power.entries, interface PWR-DC12)	7
PWR-DC12 outlet	The product gives 12 V DC at PWR-DC12 outlets to modules (power.outlets, interface PWR-DC12)	3
VID-75	The product has a video sync port behind the panel, or is a coaxial cable	9
COAX-IN	The product takes video sync at a rear COAX-IN (video_75.ports)	1
COAX-OUT	The product gives video sync it generates at a rear COAX-OUT (video_75.ports)	1
COAX-THRU	The product passes the video sync on at a rear COAX-THRU, buffered or looped (video_75.ports)	2
VIDEO	The module has a VIDEO patch jack (module.ports)	4

VID-75 covers only the video sync ports behind the panel and the coaxial cable. A coaxial picture port on the front is listed in the port list by its Annex C class.

Roles and interfaces

Every register row also names the role or interface it binds:

An interface is where two products mate: the front panel (PANEL), the rail and its screw (RAIL), the bus (PWR-BUS), a DC entry (PWR-DC12), a patch jack (PATCH), a coaxial video port (VID-75).
A role is what a product does and publishes: module, panel, enclosure, bus board, power supply, cable, and the installer of chapter 9, who assembles a system and is not a product.

A product is a composition of roles. Its product type names the main one; whatever is built in or added plays its own role and owes every requirement of it. An enclosure with a built-in supply and bus board plays enclosure, power supply, and bus board.

Distribution is a capability, not a product type. A product with PWR-DC12 outlets distributes the DC rail, and a product with buffered COAX-THRU ports beside its COAX-IN distributes the video sync, whether it is a bus board, a module, or an enclosure with these built in. It meets the outlet or port rules of what it carries, beside those of its own role: a bus board keeps the rules of its headers as well (BUS-020).

Writing the identifiers

A product type is written in lower-case words, as it reads in a sentence (power supply), and never as a code.
Every other EIS identifier is written in capitals with a hyphen: interfaces (PWR-BUS), signal classes (CV), port modes (COAX-IN), and connector variants (DC-BAR21). DC keeps its capitals as an abbreviation.

4.2 Claims

A claim is one line, EIS <edition>, <roles>:

edition: a tag of the specification's repository, or draft until the edition in work is tagged. A claim names one edition and stays valid for it when later editions change.
roles: the product type, then every other role the product plays, joined by +.

A statement that omits any of these is not an EIS claim. The claim applies to the product as a whole. Core is never written: every product meets it.

Claim line	Product
`EIS draft, module`	Any module: an oscillator, a filter, a video keyer or mixer, an encoder locked to a rear video sync port, a blank panel, or a DC entry panel; its claim file lists each port by class, and its power entries and video sync ports
`EIS draft, power supply`	Any supply: of the bus, of the DC rail (SUP-009), or both, fed from the mains or at a DC entry, including one on the back of a module that makes the bus for it from a DC rail
`EIS draft, bus board`	A bus board, with or without PWR-DC12 outlets beside its headers or the video sync tree (6.5)
`EIS draft, enclosure`	A case with nothing built in
`EIS draft, enclosure + power supply + bus board`	A case with a built-in supply and bus board, such as one fed at a case DC entry
`EIS draft, cable`	A power ribbon, a DC cable, or a coaxial cable; the claim file names the interface the cable mates. A patch cable is not an EIS product and makes no claim

Claim line grammar

The claim line in ABNF (RFC 5234), generated from the register by tools/claim.py (eis claim --grammar):

claim        = "EIS " edition ", " roles
edition      = "v" 1*DIGIT "." 1*DIGIT "." 1*DIGIT / "draft"   ; a tag of the repository, or draft until one exists
roles        = role *(" + " role)                     ; the product type, then every other role the product plays
role         = "module" / "enclosure" / "bus board" / "power supply" / "cable"

Claim file

A product publishes its EIS figures in its manual or on its product page: a module's port list (SIG-001, VID-001), width, depth, and rail currents (PANEL-003, PWR-001); a supply's rail ratings and ripple (PWR-002, SUP-001); and so on for each product type. EIS recommends keeping the claim line and all of these figures in one claim file, eis-claim.yaml, in the form of data/claim.schema.json:

eis_edition and product_type are the claim; also_claims and an enclosure's built-in supply and bus board add roles;
power lists the power entries and outlets by power interface, each with its current on every rail of that interface (6.1);
video_75 lists the video sync ports by mode;
the block of the product type (module, enclosure, and so on) carries its other figures, such as a module's port list.

The power and video_75 blocks are what bring in the register rows with a condition in brackets (4.1).

eis claim eis-claim.yaml checks that the file carries the figures the register requires of its product type that the tool knows how to check, that its classes, ranges, and formats exist, and that its header currents and ripple are inside their limits; it then prints the claim line. data/examples/ has a worked claim file for every product type.

The EIS mark

The EIS mark is the claim drawn as one block, a nameplate for a product's label, panel, or board. It is written in the claim's own words, so that the claim line reads back from it:

a solid tab at the left carries the EIS emblem knocked out, E and S hung between two rails with the I bolted to both (figures/marks/eis.svg), and under it the edition the claim names;
the plate beside the tab carries the product type as the claim writes it (MODULE, POWER SUPPLY), with one more line for each role built in.

The letters and the emblem are outlines, so the mark prints without the font. eis claim FILE --mark OUT.svg writes the mark of a claim file, and tools/marks.py draws the examples in figures/marks/.

A maker states conformance in the product's documentation, with the claim line and the date; COPYRIGHT.md sets when the statement and the mark may be used.

4.3 Verification

EIS defines interfaces and limits, not factory test procedures. A maker demonstrates conformance by inspection and measurement against the figures and tables of the normative clauses, or by documented analysis, and documents how. Annex A describes typical measurements and adds no requirements. The tests compare selected EIS figures with external publications; a test does not change a requirement.