Multi-Sensor Touch Counter

How the Multi-Sensor Touch Counter Works

The Multi-Sensor Touch Counter tracks several touch sensor channels at once and keeps a separate count for each channel. A 12-channel board such as the MPR121 reports all channels in one message.

1. Connect a multi-channel board: Use a board with several touch inputs, such as an MPR121 (12 channels) or an ESP32 (up to 10 touch pins).
2. Name the channels: Label each channel, such as Pad A to Pad L.
3. Touch the pads: Each channel counts its own activations.
4. Compare channels: See per-channel totals, shares and simultaneous touches.

Multi-Sensor Touch Counter Formula

The Multi-Sensor Touch Counter reads a bitmask where each bit is 1 channel, and a channel's count rises when its bit changes from 0 to 1.

Mask(t)

Current channel states as bits

Mask(t − 1)

Previous channel states

AND NOT

Finds bits that just turned on

Example: The mask changes from 000000000101 to 000000001110. New touches = 000000001010, so channels 1 and 3 each gain 1 count.

Multi-Sensor Touch Counter Reference Table

The Multi-Sensor Touch Counter conversion table lists common multi-channel touch boards.

About the Multi-Sensor Touch Counter

A Multi-Sensor Touch Counter is a hardware counter that tallies activations on several touch channels separately.

Multi-channel boards report all channel states as one number, called a bitmask. Comparing the current mask with the previous one finds new touches on every channel in a single step.

Ways to Use the Multi-Sensor Touch Counter

The Multi-Sensor Touch Counter has 5 key uses, including touch pianos and exhibit walls.

• ✓Touch pianos: Makers count presses on each of 12 keys.
• ✓Exhibit walls: Museums compare touches across several displays.
• ✓Voting boards: Events count votes on separate touch pads.
• ✓Reaction games: Players hit lit pads, and each pad counts hits.
• ✓Sensor comparison: Engineers compare sensitivity across channels.