Protocol

The entries of a scanner protocol, and the text blocks that carry them between the design calls and the scanner interpreter.

A protocol entry has a kind, a current value and the schema the scanner UI presents it with: a range and increment for a numeric entry, and options for a dropdown. Times are integer microseconds, the unit of the scanner’s time parameters. A preset is a negative value that the UI shows as a word and that a scanner sequence maps to a design choice, such as the shortest echo time. The grammar of the blocks is the one pulseg_protocol_parse reads on the interpreter side.

Entries

Object	Description
Parameter	One protocol entry: kind, current value and UI schema.
Kind	Type tag of an entry on the wire.
InputMode	Presentation of an entry in the scanner UI: typed in, chosen from a dropdown, or not editable.
TEPreset	Echo-time presets.
TRPreset	Repetition-time presets.

Parameter names

The names of the interpreter’s parameter table, grouped by the value type the table declares, and the options of its string-list parameters. A scanner sequence names its entries with them. Each name is a member of a StrEnum, so a key is a str that equals and hashes as its wire name; the keys of a protocol stay members until a wire block formats them.

Object	Description
ProtocolKey	A key of the protocol: a member of any of the key enums below.
UIParam	Collects the keys of every UI control, and returns the user-entry keys.
FloatKey	Keys declared as float.
IntKey	Keys declared as integer.
BoolKey	Keys declared as boolean.
EnumKey	Keys declared as string lists.
ConfigKey	Keys the sequence declares to the interpreter rather than shows.
UserKey	Keys of the float user entries, user0_value to user18_value.
UserNameKey	Keys of the descriptions naming the user entries, user0_name to user18_name.
SequenceType	Options of sequence_type.
ImagingMode	Options of imaging_mode.
PreparationType	Options of preparation_type.
TriggerType	Options of trigger_type: Pulseq trigger channel names.

Prescription

The field-of-view offset and orientation the interpreter fills from the scanner’s prescription. The entries close every listing and are not bound to a design argument; the host applies the offset when it builds the IR, and checks the design in the physical frame the orientation gives.

Object	Description
PRESCRIPTION	Keys of every prescription entry: the offset’s, then the rotation’s.
FOV_OFFSET	Keys of the field-of-view offset entries, in mm along the logical readout, phase and slice axes.
FOV_ROTATION	Keys of the rotation entries, row-major: element (i, j) of R in physical = R logical.
prescribed_offset	Field-of-view offset that protocol values carry, in metres.
prescribed_rotation	Rotation from logical to physical axes that protocol values carry, made orthonormal.

Wire blocks

A listing carries every entry with its schema, as the list design call replies it; a value block carries values only, as the validate and generate calls read and reply them. These functions are the only place where keys and values become text and text becomes them. The parsers return the key members for the names they read, and a value block parsed against a listing returns each string list as one of the listing’s options.

The RF blocks follow a reply when the call asks for them: [RfDefinitions] after the listing and [RfLayout] after the value block of a valid validation. Their readers ignore every other block, and the readers of the listing and the value block ignore these.

Object	Description
PROTOCOL_BEGIN	First line of every protocol block.
PROTOCOL_END	Last line of every protocol block.
format_listing	Format a protocol with its schema.
parse_listing	Read a protocol with its schema from a listing block.
format_values	Format a value block.
parse_values	Read a value block against the listing it was edited from.
format_prescription	Format prescription entries as the name: value lines of a block.
parse_prescription	Read the prescription entries out of the name: value lines of a block.
Validation	Reply to VALIDATE: validity, scan time, information line, values and the RF layout of a valid evaluation.
format_validation	Format a VALIDATE reply.
parse_validation	Read a VALIDATE reply.
RfDefinitionRecord	One RF definition of an [RfDefinitions] block.
format_rf_definitions	Format the RF definitions of an evaluation, as the list design call replies them.
parse_rf_definitions	Read the [RfDefinitions] block of a list reply.
RfLayoutRecord	The contents of an [RfLayout] block, one entry per instance of one TR in play order.
format_rf_layout	Format the RF layout of a validation, as the validate design call replies it.
parse_rf_layout	Read the [RfLayout] block of a validate reply.