07 - Block reference

Every block, every pin. For what they are for, see
04 - Registers and 05 - Topics.

Thirteen function blocks.

Every block but BEEBUS_NODE itself takes the node on a NODE in-out pin and returns
ERROR and STATUS. The pin must be assigned at every call — leaving it out
is a compile error.

BEEBUS_NODE

Starts the node. Call it before any other BeeBus block. TRANSPORT picks the
family, and pins the other family uses are ignored.

Runtime transports — BEEBUS_NODE_RUNTIME_UDP, BEEBUS_NODE_RUNTIME_SERIAL:

Arduino transports — BEEBUS_NODE_ARDUINO_SERIAL, BEEBUS_NODE_ARDUINO_WIFI,
BEEBUS_NODE_ARDUINO_ETHERNET — take BAUD and GROUP / UDP_PORT here, and
the board's own settings (port, pins, WiFi, Ethernet) on
BEEBUS_ARDUINO.

A failed open (BEEBUS_NOT_INITIALISED) is tried again after 1 s, 2, 4, 8, 16,
then every 30 s, until it opens. A wrong setting (BEEBUS_INVALID_ARGUMENT) is
reported once and not retried.

BEEBUS_ARDUINO

The settings only a board has. Optional, and ignored entirely on the Runtime.
Put it in the same program as the node, above or below it.

board( NODE := node, PORT := 1, RX_PIN := 18, TX_PIN := 17 );
wifi ( NODE := node, WIFI_SSID := 'plant', PASSWORD := 'secret' );

BEEBUS_NODE_STATUS

This node and its segment. Nothing here is a setting.

BEEBUS_NODE_PEER_STATUS

One peer.

BEEBUS_TP_TOPIC

A topic this node owns. No request pin — the node publishes it on its own.

Types: BOOL, SINT, USINT, BYTE, INT, UINT, WORD, DINT, UDINT,
DWORD, LINT, ULINT, LWORD, REAL, LREAL, LTIME (LINT ns),
STRING. WSTRING is BEEBUS_INVALID_ARGUMENT.

BEEBUS_TP_SUBSCRIBE

Binds a peer's topic and asks for a stream of it.

BEEBUS_TP_STRUCT

A whole STRUCT as topics this node owns, one per member. No request pin.

With WRITABLE a peer's write is queued by the node and taken in this block's
scan, one per member a scan, oldest first (as Sparkplug WRITABLE). The queue
is sized from the program: a waiting write for every WRITABLE member at once
(at least 32). Any number of WRITABLE STRUCTs, on any number of nodes; every
BOOL member can be a momentary command (PULSE) at the same time.

Names: the member path, hmi.systemMode, spare[1] (position from 1), at
most 255 characters, PREFIX included. An ARRAY on VALUE is named from the
element on: PREFIX 'alarms' gives alarms[3].set.prot.delay. Types as BEEBUS_TP_TOPIC, plus TIME/TOD (DINT ms)
and DT/DATE (UDINT seconds since 1970).

BEEBUS_TP_STRUCT_SUBSCRIBE

A peer's BEEBUS_TP_STRUCT, into a STRUCT of the same type.

BEEBUS_TP_WRITE

Writes one value into a topic a peer owns (a WRITABLE member), on a rising
edge of REQ.

BEEBUS_TP_PUBLISH

Owns a topic and sends it on a rising edge of REQ.

BEEBUS_TP_BUFFER

Holds samples of one owned topic while there is nowhere to send them.

BEEBUS_TP_SERVE

A whole STRUCT served by this node, which decides every change a peer asks
for; the owner side of BEEBUS_TP_BIND. See
11 - Settings both ways.

BEEBUS_TP_BIND

A STRUCT kept equal to the one a peer serves. Change a member and the owner
is asked; whatever it decides, the member ends with its value.

BEEBUS_MB_MAP

Puts your variables at Modbus addresses. No request pin — the variable is
the register.

ON_LOSS needs FAILSAFE := TRUE on the node block, and applies to a single
writable number — not a range, a STRUCT or a string. SAFE_VALUE is in the
number's own type: 5 on a REAL is 5.0.

BEEBUS_MB_READ

Reads a peer's registers or coils.

BEEBUS_MB_WRITE

Writes to a peer.

The VALUE pin

BEEBUS_MB_MAP, BEEBUS_MB_READ and BEEBUS_MB_WRITE all take the variable itself:

VALUE := iSetpoint        (* one address *)
VALUE := aTrend           (* ARRAY [0..99] OF WORD — a range of registers *)
VALUE := aValves          (* ARRAY [0..7] OF BOOL  — a range of coils *)
VALUE := CFG              (* a STRUCT — its members, one after the other *)

TABLE says whether the addresses are bits or registers, so the variable does
not have to. An array must have fixed bounds — ARRAY [*] is a view rather
than a variable and cannot ride a generic pin. A literal has nothing to point
at and is refused.

Each value takes its own width: BOOL, SINT, USINT, BYTE, INT, UINT,
WORD one register; DINT, UDINT, DWORD, REAL, TIME, TOD, DT,
DATE two, LINT, ULINT, LWORD, LREAL, LTIME four, high word
first; STRING(n) n/2 + 1. A bit list takes BOOLs only. WSTRING is
BEEBUS_INVALID_ARGUMENT. See 04 - Registers.

The enumerations