> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lagerdata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# ADC

> Read analog-to-digital converter values

Read analog-to-digital converter (ADC) values from your box. Supports LabJack T7 and MCC USB-202 hardware with per-hardware channel naming and voltage ranges.

## Syntax

```bash theme={null}
lager adc [NET] [OPTIONS]
```

## Arguments

| Argument | Description                                              |
| -------- | -------------------------------------------------------- |
| `NET`    | Name of the ADC net to read (optional if default is set) |

## Options

| Option       | Description                 |
| ------------ | --------------------------- |
| `--box TEXT` | Lagerbox name or IP address |
| `--help`     | Show help message and exit  |

## Usage

### Read ADC Value

Read voltage from an ADC net:

```bash theme={null}
lager adc SENSOR_1 --box my-box
```

**Output:**

```
ADC 'SENSOR_1': 2.450000 V
```

The result is returned in volts with 6 decimal places.

### List ADC Nets

When invoked without a net name (and no default is set), lists all available ADC nets:

```bash theme={null}
lager adc --box my-box
```

**Output:**

```
Name            Net Type  Instrument       Channel  Address
================================================================
VOLTAGE_SENSOR  adc       LabJack_T7       AIN0     USB::470026574
TEMP_SENSOR     adc       LabJack_T7       AIN1     USB::470026574
CURRENT_MON     adc       MCC_USB202       CH0      USB0::0x09DB::0x012B::...
```

## Supported Hardware

| Manufacturer          | Model   | Channels        | Voltage Range | Input Mode   |
| --------------------- | ------- | --------------- | ------------- | ------------ |
| LabJack               | T7      | 14 (AIN0-AIN13) | +/-10 V       | Single-ended |
| Measurement Computing | USB-202 | 8 (CH0-CH7)     | +/-10 V       | Single-ended |

### Hardware Comparison

| Feature          | LabJack T7                          | MCC USB-202                       |
| ---------------- | ----------------------------------- | --------------------------------- |
| Channel count    | 14                                  | 8                                 |
| Channel names    | AIN0-AIN13                          | CH0-CH7                           |
| Pin input format | `0`-`13` or `AIN0`-`AIN13`          | `0`-`7` or `CH0`-`CH7`            |
| Voltage range    | +/-10 V (bipolar)                   | +/-10 V (bipolar)                 |
| Resolution       | 16-bit (\~0.3 mV/LSB)               | 12-bit (\~4.9 mV/LSB)             |
| Connection       | Shared handle (with DAC, GPIO, SPI) | Per-transaction open/close        |
| Device selection | Auto-discovered (no address needed) | Via serial number or VISA address |

### Channel Naming

When creating ADC nets, the channel name depends on the hardware:

**LabJack T7:**

```bash theme={null}
# Both forms accepted:
lager nets create SENSOR_1 adc AIN0 USB::470026574
lager nets create SENSOR_1 adc 0 USB::470026574    # Numeric shorthand
```

Numeric pins `0`-`13` map to `AIN0`-`AIN13` internally.

**MCC USB-202:**

```bash theme={null}
# Both forms accepted (case-insensitive):
lager nets create SENSOR_1 adc CH0 USB0::0x09DB::...
lager nets create SENSOR_1 adc 0 USB0::0x09DB::...  # Numeric shorthand
```

Numeric pins `0`-`7` and named pins `CH0`-`CH7` are both accepted. Channel names are case-insensitive.

### Instrument Name Matching

The backend driver is selected based on the instrument name in the net configuration:

| Pattern                                                       | Driver      |
| ------------------------------------------------------------- | ----------- |
| `labjack` + `t7` (case-insensitive, flexible separators)      | LabJack T7  |
| `mcc` + `usb` + `202` (case-insensitive, flexible separators) | MCC USB-202 |

## Default Net

Set a default ADC net to avoid specifying the name each time:

```bash theme={null}
lager defaults add --adc-net SENSOR_1
```

Then:

```bash theme={null}
lager adc
```

## Examples

```bash theme={null}
# Read ADC value from voltage sensor
lager adc VOLTAGE_SENSOR --box my-box

# Read ADC value from temperature sensor
lager adc TEMP_SENSOR --box my-box

# Read ADC value from current monitor
lager adc CURRENT_MONITOR --box my-box

# List all ADC nets on the box
lager adc --box my-box

# Use default net (if configured)
lager adc
```

## Scripting Example

```bash theme={null}
#!/bin/bash
# Read sensor and check threshold
RESULT=$(lager adc VOLTAGE_SENSOR --box my-box)
echo "$RESULT"

# Extract numeric value
VOLTAGE=$(echo "$RESULT" | grep -oP '[\d.]+(?= V)')
if (( $(echo "$VOLTAGE > 3.0" | bc -l) )); then
    echo "Voltage too high: $VOLTAGE V"
    exit 1
fi
echo "Voltage OK: $VOLTAGE V"
```

## Notes

* Results are returned in volts with 6 decimal places
* Both hardware backends support bipolar measurement (+/-10 V range)
* ADC nets must be configured before use with `lager nets create <name> adc <channel> <address>`
* Default net can be set with `lager defaults add --adc-net`
* LabJack T7 shares a connection handle with DAC, GPIO, and SPI operations on the same device
* USB-202 opens and closes the connection on each read
* Use `lager instruments --box <box>` to verify the ADC device is detected

## See Also

* [DAC](/source/reference/cli/dac) -- Digital-to-analog converter output (the complement of ADC)
* [Python ADC API](/source/reference/python/adc) -- Read ADC values in Python scripts