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The Simple Desk provides a fast and intuitive way to control DMX channels directly without creating scenes or functions. It’s designed for quick setup and live control scenarios.

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Overview

Simple Desk acts as a DMX source that allows you to:
  • Control individual DMX channels with sliders
  • Override running functions for specific channels
  • Dump channel values to create new scenes
  • Use keypad commands for rapid channel control

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Channel Control

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Direct Value Setting

The Simple Desk displays all 512 channels for the selected universe. You can adjust any channel by:
  1. Selecting a universe from the universe filter
  2. Moving the slider for the desired channel
  3. The channel value is immediately written to DMX output
When Simple Desk controls a channel, it sets the Override flag. This means the Simple Desk value takes priority over other functions trying to control the same channel.

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Channel Display

Channels are displayed with the following information:
  • Channel index: Relative to the fixture (0-based)
  • Current value: DMX value (0-255)
  • Override status: Indicates if Simple Desk is controlling the channel
  • Fixture reference: Shows which fixture owns the channel
// From simpledesk.cpp:200
void SimpleDesk::setValue(quint32 fixtureID, uint channel, uchar value)
{
    // Set value with override flag
    m_values[start + channel] = value;
    fc->addFlag(FadeChannel::Override);
}

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Keypad Commands

Simple Desk includes a powerful keypad parser for rapid channel control. The keypad accepts commands like:
  • 1 @ 50 - Set channel 1 to 50%
  • 1 THRU 10 @ FULL - Set channels 1-10 to full
  • 1 + 5 + 10 @ 0 - Set channels 1, 5, and 10 to zero
The keypad maintains a history of your last 10 commands, accessible through the command history.

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Command History

The Simple Desk tracks your recent keypad commands: 
// From simpledesk.cpp:542
m_keypadCommandHistory.prepend(command.toUpper());
if (m_keypadCommandHistory.count() > MAX_KEYPAD_HISTORY)
    m_keypadCommandHistory.removeLast();

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Dumping to Scene

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Channel Selection

As you adjust channels in Simple Desk, they’re automatically added to a dump list. This allows you to:
  1. Adjust multiple channels to create a look
  2. Select which channel types to include (dimmer, color, position, etc.)
  3. Dump the selected channels to a new or existing scene

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Dump Options

// From simpledesk.cpp:506
void SimpleDesk::dumpDmxChannels(QString name, quint32 mask, 
                                  int sceneID, bool nonZeroOnly)
{
    m_functionManager->dumpDmxValues(m_dumpValues, fixtureList, 
                                     mask, name, sceneID, nonZeroOnly);
}
The dump functionality provides:
  • Channel type filtering: Choose dimmer, color, position, gobo, etc.
  • Non-zero filtering: Optionally exclude channels set to zero
  • Scene selection: Create new scene or update existing one
1

Adjust Channels

Use sliders or keypad to set desired channel values
2

Select Channel Types

Choose which channel types to include in the dump
3

Dump to Scene

Click “Dump” and select target scene or create new one

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Universe Management

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Universe Selection

Simple Desk operates on one universe at a time. The universe filter allows you to:
  • Switch between available universes
  • View only fixtures in the selected universe
  • Control channels 0-511 for that universe

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Reset Operations

Reset Channel: Removes Simple Desk control from a single channel and restores its default value. 
// From simpledesk.cpp:285
void SimpleDesk::resetChannel(uint channel)
{
    m_values.remove(start + channel);
    // Command queued for execution in writeDMX
    m_commandQueue.append(QPair<int,quint32>(ResetChannel, start + channel));
}
Reset Universe: Clears all Simple Desk overrides for the entire universe. 
// From simpledesk.cpp:258
void SimpleDesk::resetUniverse(int universe)
{
    // Remove all values for this universe
    // Reset channels to default values
    m_commandQueue.append(QPair<int,quint32>(ResetUniverse, universe));
}

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Integration with Web Access

Simple Desk is fully accessible through the Web Access interface, allowing remote control via:
  • Web browser on any device
  • Touch-friendly interface for tablets
  • Multiple simultaneous connections
// From simpledesk.h:110
// Web access helpers (absolute address based)
int getSlidersNumber() const;
uchar getAbsoluteChannelValue(uint address) const;
void setAbsoluteChannelValue(uint address, uchar value);

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DMX Source Implementation

Simple Desk implements the DMXSource interface, making it part of the QLC+ engine’s rendering pipeline: 
// From simpledesk.cpp:575
void SimpleDesk::writeDMX(MasterTimer *timer, QList<Universe *> ua)
{
    // Process reset commands
    // Write overridden channel values with faders
    FadeChannel *fc = getFader(ua, uni, fxID, channel);
    fc->setCurrent(value);
    fc->setTarget(value);
    fc->addFlag(FadeChannel::Override);
}
Simple Desk uses the GenericFader system to ensure smooth value transitions and proper priority handling with other DMX sources.

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Best Practices

  • Live Control: Use Simple Desk for quick adjustments during live shows
  • Scene Creation: Build scenes by adjusting channels and dumping to scenes
  • Testing: Quickly test fixture functionality without programming
  • Override Control: Temporarily override automated functions
  • Keypad Efficiency: Learn keypad commands for faster workflow

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Technical Details

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Channel Storage

Simple Desk maintains a hash map of only the channels it’s controlling: 
// From simpledesk.h:132
// Only channels overridden by Simple Desk are stored
QHash <uint,uchar> m_values;
This efficient approach means:
  • Minimal memory usage
  • Fast channel lookups
  • Easy to determine which channels are overridden

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Thread Safety

All channel operations are protected by mutex locks to ensure thread safety: 
// From simpledesk.cpp:241
QMutexLocker locker(&m_mutex);

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