Instrument readouts and controls

Bit Field `<smart-bit-field>`

BitField displays a fixed-width register as individual bits with names, keeping the word value and the bits in sync.

JavaScript TypeScript Angular React Vue Blazor

<smart-bit-field> · 8 properties, 3 methods, 1 events · source/modules/smart.bitfield.js

Usage in Blazor

The Razor component is <BitField> in Smart.Blazor.Industrial: every property is a parameter in PascalCase, every event an EventCallback<Event> named On<Event> whose ev["Detail"] is the typed detail class, and the methods are called on the @ref. String choices are enums. In a Blazor Web App (.NET 8 and later) the page needs an interactive render mode, for example @rendermode InteractiveServer; a statically rendered component stays empty.

@using Smart.Blazor.Industrial
@* .NET 8 and later: an interactive render mode, on the page or for the whole app *@
@rendermode InteractiveServer

<BitField @ref="bitField" Interactive="true" Interactive="true"
    OnChange="OnChange" />

@code {
    BitField bitField;

    void OnChange(Event ev)
    {
        BitFieldChangeEventDetail detail = ev["Detail"];
    }

    // Task<bool> Bit(int index)
    void Call() => bitField.Bit(42);
}

Properties

Parameter	Type, default	Description
`BitOrder` bitOrder	BitFieldBitOrder msbFirst	Sets or retrieves the display order of the bits. It affects the display only; bits are always numbered from the least significant bit, so bit 3 is the same bit in both orders.
`Bits` bits	IEnumerable<object>	Sets or retrieves the register map, as [{ index, label, description, readOnly, color }]. index counts from the least significant bit. A bit marked readOnly refuses to change, a register map is a contract, and a UI that lets an operator flip a reserved bit is lying about the hardware. An entry that is not an object is skipped.
`GroupSize` groupSize	int 4	Sets or gets the number of bits grouped together visually. Groups are counted from the least significant end, so nibble boundaries line up with the hexadecimal digits underneath. 0 removes the grouping.
`Interactive` interactive	bool false	Sets or retrieves whether the bits can be toggled by click or keyboard. The property is named for the enabled state because boolean attributes are presence-based, and a property that defaulted to true could not be turned off from markup. When false the bits are not buttons and not in the tab order.
`RadixDisplay` radixDisplay	BitFieldRadixDisplay hex	Sets or retrieves how the word value is written beneath the bits.
`ShowIndices` showIndices	bool true	Sets or retrieves whether each bit shows its number. Boolean attributes are presence-based, so set the property from script to turn it off.
`Value` value	object 0	Sets or retrieves the word. Accepts a number, a BigInt, a boolean, or a string with an optional sign and 0x, 0b or 0o prefix (-0x1 is minus one; 1e3 is 1000); a negative value is treated as two's complement. The value is read back as a decimal string - signed for a signed word length, so an int16 at all ones reads -1 - because a 64-bit value cannot be represented exactly as a number. A value wider than the word length is masked, and one that cannot be read becomes 0: whatever was assigned, the property reads back in this form.
`WordLength` wordLength	BitFieldWordLength uint16	Sets or retrieves the register width and signedness. Signedness shows only in the decimal readout: the same bit pattern is 65535 as a uint16 and -1 as an int16.

Methods

Method	Description
`Task<bool> Bit(int index)`	Returns the value of one bit. The index counts from the least significant bit regardless of the bitOrder property. `index` number Bit position from the least significant bit.
`void Mask(object mask)`	Sets or clears every bit that is set in the mask, as a "clear faults" command does. A bit marked readOnly in the register map is not changed, and bits beyond the word length are ignored. `mask` number \| string \| bigint The bits to act on. `on` boolean Set them (the default) or clear them.
`void SetBit(int index)`	Sets, clears or toggles one bit. A bit marked readOnly in the register map is not changed. `index` number Bit position from the least significant bit. `on` boolean Force a state instead of toggling.

Events

Every event is an EventCallback<Event>; Event is a dictionary and ev["Detail"] converts to the detail class named under the event.

Event	Description and detail
`OnChange` change BitFieldChangeEventDetail	This event is triggered when the word changes through the component, a click, the keyboard, setBit or mask. Assigning the value property directly does not raise it. `Value` string The new word, as a decimal string. `OldValue` string The previous word. `Bit` int Which bit changed, or null when a mask changed several at once.

Types

`enum BitFieldBitOrder`

BitFieldBitOrder.MsbFirst "msbFirst" BitFieldBitOrder.LsbFirst "lsbFirst"

`enum BitFieldRadixDisplay`

BitFieldRadixDisplay.Hex "hex" BitFieldRadixDisplay.Dec "dec" BitFieldRadixDisplay.Bin "bin" BitFieldRadixDisplay.Oct "oct" BitFieldRadixDisplay.None "none"

`enum BitFieldWordLength`

BitFieldWordLength.Int8 "int8" BitFieldWordLength.Uint8 "uint8" BitFieldWordLength.Int16 "int16" BitFieldWordLength.Uint16 "uint16" BitFieldWordLength.Int32 "int32" BitFieldWordLength.Uint32 "uint32" BitFieldWordLength.Int64 "int64" BitFieldWordLength.Uint64 "uint64"

CSS variables

The component declares 5 CSS variables; the CSS page shows how to set them.

--smart-bit-size --smart-bit-off-color --smart-bit-on-color --smart-bit-gap --smart-bit-group-gap