AEM Commands #

Use the AEM commands to measure current, voltage, and temperature, as well as to calibrate the AEM.

For more information about AEM see the AEM overview.


Commands	Description	Supported on
aem calibrate	Perform AEM calibration.
aem avg	Measure current in block averages.
aem calinfo	Get AEM calibration info.
aem temp	Get external temperature sensor reading.
aem current	Print the average current.
aem info	Display AEM information.
aem statistics	Run a measurement and print statistics.
aem voltage	Print the voltage.

aem calibrate #

Manually runs the AEM calibration. VMCU is disabled during AEM calibration.

Command Line Syntax

$ aem calibrate$ aem calibrate

Command Line Example

$ aem calibrate
Calibrating...OK!
=== Calibration Info ===
 - Low Range -
  HG Offset cal/uncal [diff]: -0.0187/-0.0183 [-0.0004] mA
  LG Offset cal/uncal [diff]: -0.0185/-0.0183 [-0.0002] mA
 - High Range -
  LG Offset cal/uncal [diff]: -0.0438/-0.0183 [-0.0255] mA
 Temperature at last calibration: 37.64 deg C
 Cal. no:      2
 Time (local): 258376760938 us
 VMCU:         3.300 V
 Cal. samples: 1000000 samples
 --- Calibration point 0 ---
  Cal. resistance: 4.707000e+02 Ohm
  Expected:        6.989581 mA
  High Gain:       3.999031 mA
  Low gain:        7.033418 mA
 --- Calibration point 1 ---
  Cal. resistance: 2.200070e+04 Ohm
  Expected:        0.149504 mA
  High Gain:       0.168107 mA
  Low gain:        0.168035 mA
 --- Calibration point 2 ---
  Cal. resistance: 1.000000e+12 Ohm
  Expected:        0.000000 mA
  High Gain:       0.018725 mA
  Low gain:        0.021894 mA$ aem calibrate
Calibrating...OK!
=== Calibration Info ===
 - Low Range -
  HG Offset cal/uncal [diff]: -0.0187/-0.0183 [-0.0004] mA
  LG Offset cal/uncal [diff]: -0.0185/-0.0183 [-0.0002] mA
 - High Range -
  LG Offset cal/uncal [diff]: -0.0438/-0.0183 [-0.0255] mA
 Temperature at last calibration: 37.64 deg C
 Cal. no:      2
 Time (local): 258376760938 us
 VMCU:         3.300 V
 Cal. samples: 1000000 samples
 --- Calibration point 0 ---
  Cal. resistance: 4.707000e+02 Ohm
  Expected:        6.989581 mA
  High Gain:       3.999031 mA
  Low gain:        7.033418 mA
 --- Calibration point 1 ---
  Cal. resistance: 2.200070e+04 Ohm
  Expected:        0.149504 mA
  High Gain:       0.168107 mA
  Low gain:        0.168035 mA
 --- Calibration point 2 ---
  Cal. resistance: 1.000000e+12 Ohm
  Expected:        0.000000 mA
  High Gain:       0.018725 mA
  Low gain:        0.021894 mA

aem avg #

Gets the latest block average current measurement from the AEM.

Use the option -r to enable repeated measurements, with one averaged value reported every 20 milliseconds. The PK has a new block average ready roughly every 25 ms, while the WPK has a new block average ready roughly every 4 ms. Send a new line to exit the loop.

Command Line Syntax

$ aem avg [-r]$ aem avg [-r]

Command Line Example

$ aem avg
0.000076 mA$ aem avg
0.000076 mA

aem calinfo #

Retrieves information about the active calibration. If the externally measured temperature or the configured voltage has changed significantly, a recommendation to recalibrate the AEM will be displayed.

Command Line Syntax

$ aem calinfo$ aem calinfo

Command Line Example

$ aem calinfo
=== Calibration Info ===
 - Low Range -
  HG Offset cal/uncal [diff]: -0.0187/-0.0183 [-0.0004] mA
  LG Offset cal/uncal [diff]: -0.0175/-0.0183 [00.0008] mA
 - High Range -
  LG Offset cal/uncal [diff]: -0.0317/-0.0183 [-0.0133] mA
 Temperature at last calibration: 24.20 deg C
 Cal. no:      1
 Time (local): 87930 us
 VMCU:         3.300 V
 Cal. samples: 1000000 samples
 --- Calibration point 0 ---
  Cal. resistance: 4.707000e+02 Ohm
  Expected:        6.990707 mA
  High Gain:       4.004747 mA
  Low gain:        7.022371 mA
 --- Calibration point 1 ---
  Cal. resistance: 2.200070e+04 Ohm
  Expected:        0.149539 mA
  High Gain:       0.168258 mA
  Low gain:        0.167082 mA
 --- Calibration point 2 ---
  Cal. resistance: 1.000000e+12 Ohm
  Expected:        0.000000 mA
  High Gain:       0.018728 mA
  Low gain:        0.020252 mA
AEM should be recalibrated due to a temperature change since last calibration from 24.20 deg C to 37.91 deg C$ aem calinfo
=== Calibration Info ===
 - Low Range -
  HG Offset cal/uncal [diff]: -0.0187/-0.0183 [-0.0004] mA
  LG Offset cal/uncal [diff]: -0.0175/-0.0183 [00.0008] mA
 - High Range -
  LG Offset cal/uncal [diff]: -0.0317/-0.0183 [-0.0133] mA
 Temperature at last calibration: 24.20 deg C
 Cal. no:      1
 Time (local): 87930 us
 VMCU:         3.300 V
 Cal. samples: 1000000 samples
 --- Calibration point 0 ---
  Cal. resistance: 4.707000e+02 Ohm
  Expected:        6.990707 mA
  High Gain:       4.004747 mA
  Low gain:        7.022371 mA
 --- Calibration point 1 ---
  Cal. resistance: 2.200070e+04 Ohm
  Expected:        0.149539 mA
  High Gain:       0.168258 mA
  Low gain:        0.167082 mA
 --- Calibration point 2 ---
  Cal. resistance: 1.000000e+12 Ohm
  Expected:        0.000000 mA
  High Gain:       0.018728 mA
  Low gain:        0.020252 mA
AEM should be recalibrated due to a temperature change since last calibration from 24.20 deg C to 37.91 deg C

aem temp #

Retrieves the temperature reading from the sensor located near the AEM circuitry.

Command Line Syntax

$ aem temp$ aem temp

Command Line Example

$ aem temp
Temperature: 38.84 C$ aem temp
Temperature: 38.84 C

aem current #

Retrieves the average current from the AEM.

Use the option -r for repeating measurements, with one averaged measurement reported per second. Send a new line to exit the loop. The output also includes the raw low gain (LG) and high gain (HG) current measurements.

Command Line Syntax

$ aem current$ aem current

Command Line Example

$ aem current
AEM current: 7.77 mA    [LG: 7.8073] [HG: 0.5820]$ aem current
AEM current: 7.77 mA    [LG: 7.8073] [HG: 0.5820]

aem info #

Displays miscellaneous AEM information.

Command Line Syntax

$ aem info$ aem info

Command Line Example

$ aem info
Filter mode             : average [2]
AEM LG lp filter length : 65
AEM LG lp filter gain   : 32796
AEM HG lp filter length : 65
AEM HG lp filter gain   : 32796
HG offset: 0.000
HG bias  : 15.070 uA
LG offset: 0.000
LG bias  : 0.041 mA$ aem info
Filter mode             : average [2]
AEM LG lp filter length : 65
AEM LG lp filter gain   : 32796
AEM HG lp filter length : 65
AEM HG lp filter gain   : 32796
HG offset: 0.000
HG bias  : 15.070 uA
LG offset: 0.000
LG bias  : 0.041 mA

aem statistics #

Runs measurements over a specified number of samples and prints statistics for the measurements. If the number of samples is not specified, 10,000 samples will be collected.

Command Line Syntax

$ aem statistics [ samples ]$ aem statistics [ samples ]

Command Line Example

$ aem statistics
Sample Count: 10000
       Mean                                Standard deviation
LG:    0.5831 [mA]   26.6358 [LSB]         0.0580 [mA]    6.1549 [LSB]
HG:  582.4518 [uA] 4085.1316 [LSB]         3.2378 [uA]  490.4147 [LSB]$ aem statistics
Sample Count: 10000
       Mean                                Standard deviation
LG:    0.5831 [mA]   26.6358 [LSB]         0.0580 [mA]    6.1549 [LSB]
HG:  582.4518 [uA] 4085.1316 [LSB]         3.2378 [uA]  490.4147 [LSB]

aem voltage #

Retrieves the currently measured voltage.

Use the option -r for repeating measurements, with one measurement every 100 milliseconds. Send a new line to exit the loop.

Two voltages are printed:

The first is the voltage measured when the last current measurement completed.
The second (in brackets) is the voltage measured at the time the command was executed.

Command Line Syntax

$ aem voltage$ aem voltage

Command Line Example

$ aem voltage
AEM voltage: 3.3529 [3.3534]$ aem voltage
AEM voltage: 3.3529 [3.3534]