IOCAN

# Map Input

## Overview

A **Map Input** applies a **1D lookup table** to another input and reports the

result as a new, independent channel. You give it a list of X breakpoints and the

Y value at each one; the controller looks up the source value on the X axis and

**interpolates** between points. Use it to reshape a signal — for example to turn

a pedal-position input into a torque-request curve.

This is the standalone 1D map described on the

[Scaling & Maps](../Scaling-and-Maps.md) page — it produces a **separate** channel

that other IO can reference by alias.

## Prerequisites & hardware

You need:

- A **source input** to use as the X axis — any existing input, by alias.

- The map data: matching lists of **X breakpoints** and **Y values**.

## Add it in the app

1. Add a new input and choose **Map Input** as the type.

2. Choose the **source input** (the X axis).

3. Give it a clear **alias** (e.g. `Torque Request`).

4. Enter the **input values** (X) and **output values** (Y) of the map.

## Settings reference

> Schema: `config/MapInputConfigData.proto`.

| Setting | Meaning | Unit | Range / values | Notes |

|---|---|---|---|---|

| **Source input** | The input read on the X axis | — | an existing input (by alias) | The value looked up in the map. |

| **Input values (X)** | The X-axis breakpoints | source's unit | list of sint32 | Must be **strictly increasing**. The points where the curve bends. |

| **Output values (Y)** | The result at each X breakpoint | result's unit | list of sint32 | One Y per X. Values between breakpoints are interpolated. |

**How it maps:** the source value is located between two X breakpoints and the

output is linearly interpolated between their Y values. Keep one Y for every X.

For more on editing maps, see [Scaling & Maps](../Scaling-and-Maps.md).

## Common settings

Map Input also uses the shared setting — alias. See [Common IO Settings](../Common-IO-Settings.md).

## Example — pedal position to torque request

1. Type **Map Input**, alias `Torque Request`.

2. **Source input** = your `Pedal Position` input (0–100 %).

3. **Input values (X)** `0, 20, 50, 80, 100`.

4. **Output values (Y)** `0, 50, 200, 450, 600` — a progressive curve that is

   gentle off-idle and steeper near full pedal.

## Troubleshooting

- **Output flat or stuck at one end:** the source is sitting below the first or

  above the last X breakpoint — values outside the table are clamped to the end Y.

- **Map rejected / behaves oddly:** make sure **Input values** are strictly

  increasing and that there is one **Output value** for each.

## Related

- [Scaling & Maps](../Scaling-and-Maps.md) — concept page for 1D maps.

- [Map Output](../outputs/Map-Output.md) — the same lookup applied to an output.

- [Mux Input](Mux-Input.md) — select between inputs rather than interpolate.