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

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:

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:

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:

# 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:

# 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:

lager defaults add --adc-net SENSOR_1

Then:

lager adc

Examples

# 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

#!/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 — Digital-to-analog converter output (the complement of ADC)
• Python ADC API — Read ADC values in Python scripts